diff --git a/lib/cloudinary/__init__.py b/lib/cloudinary/__init__.py
index 5faf1c0b..4422b38d 100644
--- a/lib/cloudinary/__init__.py
+++ b/lib/cloudinary/__init__.py
@@ -1,13 +1,15 @@
 from __future__ import absolute_import
 
+import abc
 from copy import deepcopy
+import hashlib
 import os
 import re
 import logging
 import numbers
 import certifi
 from math import ceil
-from six import python_2_unicode_compatible
+from six import python_2_unicode_compatible, add_metaclass
 
 logger = logging.getLogger("Cloudinary")
 ch = logging.StreamHandler()
@@ -34,8 +36,9 @@ AKAMAI_SHARED_CDN = "res.cloudinary.com"
 SHARED_CDN = AKAMAI_SHARED_CDN
 CL_BLANK = "data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7"
 URI_SCHEME = "cloudinary"
+API_VERSION = "v1_1"
 
-VERSION = "1.20.0"
+VERSION = "1.26.0"
 
 USER_AGENT = "CloudinaryPython/{} (Python {})".format(VERSION, python_version())
 """ :const: USER_AGENT """
@@ -94,54 +97,20 @@ def import_django_settings():
         return None
 
 
-class Config(object):
+@add_metaclass(abc.ABCMeta)
+class BaseConfig(object):
     def __init__(self):
         django_settings = import_django_settings()
         if django_settings:
             self.update(**django_settings)
-        elif os.environ.get("CLOUDINARY_CLOUD_NAME"):
-            self.update(
-                cloud_name=os.environ.get("CLOUDINARY_CLOUD_NAME"),
-                api_key=os.environ.get("CLOUDINARY_API_KEY"),
-                api_secret=os.environ.get("CLOUDINARY_API_SECRET"),
-                secure_distribution=os.environ.get("CLOUDINARY_SECURE_DISTRIBUTION"),
-                private_cdn=os.environ.get("CLOUDINARY_PRIVATE_CDN") == 'true',
-                api_proxy=os.environ.get("CLOUDINARY_API_PROXY"),
-            )
-        elif os.environ.get("CLOUDINARY_URL"):
-            cloudinary_url = os.environ.get("CLOUDINARY_URL")
-            self._parse_cloudinary_url(cloudinary_url)
 
-    def _parse_cloudinary_url(self, cloudinary_url):
-        uri = urlparse(cloudinary_url)
-        if not self._is_url_scheme_valid(uri):
-            raise ValueError("Invalid CLOUDINARY_URL scheme. Expecting to start with 'cloudinary://'")
-
-        for k, v in parse_qs(uri.query).items():
-            if self._is_nested_key(k):
-                self._put_nested_key(k, v)
-            else:
-                self.__dict__[k] = v[0]
-        self.update(
-            cloud_name=uri.hostname,
-            api_key=uri.username,
-            api_secret=uri.password,
-            private_cdn=uri.path != ''
-        )
-        if uri.path != '':
-            self.update(secure_distribution=uri.path[1:])
+        self._load_config_from_env()
 
     def __getattr__(self, i):
-        if i in self.__dict__:
-            return self.__dict__[i]
-        else:
-            return None
+        return self.__dict__.get(i)
 
-    def update(self, **keywords):
-        for k, v in keywords.items():
-            self.__dict__[k] = v
-
-    def _is_nested_key(self, key):
+    @staticmethod
+    def _is_nested_key(key):
         return re.match(r'\w+\[\w+\]', key)
 
     def _put_nested_key(self, key, value):
@@ -160,8 +129,7 @@ class Config(object):
             value = value[0]
         outer[last_key] = value
 
-    @staticmethod
-    def _is_url_scheme_valid(url):
+    def _is_url_scheme_valid(self, url):
         """
         Helper function. Validates url scheme
 
@@ -169,9 +137,81 @@ class Config(object):
 
         :return: bool True on success or False on failure
         """
-        if not url.scheme or url.scheme.lower() != URI_SCHEME:
-            return False
-        return True
+        return url.scheme.lower() == self._uri_scheme
+
+    @staticmethod
+    def _parse_cloudinary_url(cloudinary_url):
+        return urlparse(cloudinary_url)
+
+    @abc.abstractmethod
+    def _config_from_parsed_url(self, parsed_url):
+        """Extract additional config from the parsed URL."""
+        raise NotImplementedError()
+
+    def _setup_from_parsed_url(self, parsed_url):
+        config_from_parsed_url = self._config_from_parsed_url(parsed_url)
+        self.update(**config_from_parsed_url)
+
+        for k, v in parse_qs(parsed_url.query).items():
+            if self._is_nested_key(k):
+                self._put_nested_key(k, v)
+            else:
+                self.__dict__[k] = v[0]
+
+    def _load_from_url(self, url):
+        parsed_url = self._parse_cloudinary_url(url)
+
+        return self._setup_from_parsed_url(parsed_url)
+
+    @abc.abstractmethod
+    def _load_config_from_env(self):
+        """Load config from environment variables or URL."""
+        raise NotImplementedError()
+
+    def update(self, **keywords):
+        for k, v in keywords.items():
+            self.__dict__[k] = v
+
+
+class Config(BaseConfig):
+    def __init__(self):
+        self._uri_scheme = URI_SCHEME
+
+        super(Config, self).__init__()
+
+        if not self.signature_algorithm:
+            self.signature_algorithm = utils.SIGNATURE_SHA1
+
+    def _config_from_parsed_url(self, parsed_url):
+        if not self._is_url_scheme_valid(parsed_url):
+            raise ValueError("Invalid CLOUDINARY_URL scheme. Expecting to start with 'cloudinary://'")
+
+        is_private_cdn = parsed_url.path != ""
+        result = {
+            "cloud_name": parsed_url.hostname,
+            "api_key": parsed_url.username,
+            "api_secret": parsed_url.password,
+            "private_cdn": is_private_cdn,
+        }
+        if is_private_cdn:
+            result.update({"secure_distribution": parsed_url.path[1:]})
+
+        return result
+
+    def _load_config_from_env(self):
+        if os.environ.get("CLOUDINARY_CLOUD_NAME"):
+            config_keys = [key for key in os.environ.keys()
+                           if key.startswith("CLOUDINARY_") and key != "CLOUDINARY_URL"]
+
+            for full_key in config_keys:
+                conf_key = full_key[len("CLOUDINARY_"):].lower()
+                conf_val = os.environ[full_key]
+                if conf_val in ["true", "false"]:
+                    conf_val = conf_val == "true"
+
+                self.update(**{conf_key: conf_val})
+        elif os.environ.get("CLOUDINARY_URL"):
+            self._load_from_url(os.environ.get("CLOUDINARY_URL"))
 
 
 _config = Config()
@@ -257,7 +297,8 @@ class CloudinaryResource(object):
         return self.get_prep_value() + '#' + self.get_expected_signature()
 
     def get_expected_signature(self):
-        return utils.api_sign_request({"public_id": self.public_id, "version": self.version}, config().api_secret)
+        return utils.api_sign_request({"public_id": self.public_id, "version": self.version}, config().api_secret,
+                                      config().signature_algorithm)
 
     @property
     def url(self):
@@ -377,7 +418,7 @@ class CloudinaryResource(object):
         max_images = srcset_data.get("max_images", 20)
         transformation = srcset_data.get("transformation")
 
-        kbytes_step = int(ceil(float(bytes_step)/1024))
+        kbytes_step = int(ceil(float(bytes_step) / 1024))
 
         breakpoints_width_param = "auto:breakpoints_{min_width}_{max_width}_{kbytes_step}_{max_images}:json".format(
             min_width=min_width, max_width=max_width, kbytes_step=kbytes_step, max_images=max_images)
@@ -623,7 +664,7 @@ class CloudinaryResource(object):
 
         return utils.cloudinary_url(poster_options['public_id'], **poster_options)[0]
 
-    def _populate_video_source_tags(self, source,  options):
+    def _populate_video_source_tags(self, source, options):
         """
         Helper function for video tag, populates source tags from provided options.
 
@@ -750,7 +791,7 @@ class CloudinaryResource(object):
         srcset_data = srcset_data.copy()
         srcset_data.update(options.pop("srcset", dict()))
 
-        responsive_attrs  = self._generate_image_responsive_attributes(attrs, srcset_data, **options)
+        responsive_attrs = self._generate_image_responsive_attributes(attrs, srcset_data, **options)
 
         attrs.update(responsive_attrs)
 
diff --git a/lib/cloudinary/api.py b/lib/cloudinary/api.py
index 5d9da408..7c1fd534 100644
--- a/lib/cloudinary/api.py
+++ b/lib/cloudinary/api.py
@@ -1,5 +1,6 @@
 # Copyright Cloudinary
 
+import datetime
 import email.utils
 import json
 import socket
@@ -10,6 +11,11 @@ from urllib3.exceptions import HTTPError
 
 import cloudinary
 from cloudinary import utils
+from cloudinary.api_client.call_api import (
+    call_api,
+    call_metadata_api,
+    call_json_api
+)
 from cloudinary.exceptions import (
     BadRequest,
     AuthorizationRequired,
@@ -20,37 +26,32 @@ from cloudinary.exceptions import (
     GeneralError
 )
 
-logger = cloudinary.logger
-
-EXCEPTION_CODES = {
-    400: BadRequest,
-    401: AuthorizationRequired,
-    403: NotAllowed,
-    404: NotFound,
-    409: AlreadyExists,
-    420: RateLimited,
-    500: GeneralError
-}
-
-
-class Response(dict):
-    def __init__(self, result, response, **kwargs):
-        super(Response, self).__init__(**kwargs)
-        self.update(result)
-        self.rate_limit_allowed = int(response.headers["x-featureratelimit-limit"])
-        self.rate_limit_reset_at = email.utils.parsedate(response.headers["x-featureratelimit-reset"])
-        self.rate_limit_remaining = int(response.headers["x-featureratelimit-remaining"])
-
-
-_http = utils.get_http_connector(cloudinary.config(), cloudinary.CERT_KWARGS)
-
 
 def ping(**options):
     return call_api("get", ["ping"], {}, **options)
 
 
 def usage(**options):
-    return call_api("get", ["usage"], {}, **options)
+    """Get account usage details.
+
+    Get a report on the status of your Cloudinary account usage details, including storage, credits, bandwidth,
+    requests, number of resources, and add-on usage. Note that numbers are updated periodically.
+
+    See: `Get account usage details
+    <https://cloudinary.com/documentation/admin_api#get_account_usage_details>`_
+
+    :param options:     Additional options
+    :type options:      dict, optional
+    :return:            Detailed usage information
+    :rtype:             Response
+    """
+    date = options.pop("date", None)
+    uri = ["usage"]
+    if date:
+        if isinstance(date, datetime.date):
+            date = utils.encode_date_to_usage_api_format(date)
+        uri.append(date)
+    return call_api("get", uri, {}, **options)
 
 
 def resource_types(**options):
@@ -64,7 +65,7 @@ def resources(**options):
     if upload_type:
         uri.append(upload_type)
     params = only(options, "next_cursor", "max_results", "prefix", "tags",
-                  "context", "moderations", "direction", "start_at")
+                  "context", "moderations", "direction", "start_at", "metadata")
     return call_api("get", uri, params, **options)
 
 
@@ -72,7 +73,7 @@ def resources_by_tag(tag, **options):
     resource_type = options.pop("resource_type", "image")
     uri = ["resources", resource_type, "tags", tag]
     params = only(options, "next_cursor", "max_results", "tags",
-                  "context", "moderations", "direction")
+                  "context", "moderations", "direction", "metadata")
     return call_api("get", uri, params, **options)
 
 
@@ -80,7 +81,7 @@ def resources_by_moderation(kind, status, **options):
     resource_type = options.pop("resource_type", "image")
     uri = ["resources", resource_type, "moderations", kind, status]
     params = only(options, "next_cursor", "max_results", "tags",
-                  "context", "moderations", "direction")
+                  "context", "moderations", "direction", "metadata")
     return call_api("get", uri, params, **options)
 
 
@@ -92,12 +93,39 @@ def resources_by_ids(public_ids, **options):
     return call_api("get", uri, params, **options)
 
 
+def resources_by_context(key, value=None, **options):
+    """Retrieves resources (assets) with a specified context key.
+    This method does not return deleted assets even if they have been backed up.
+
+    See: `Get resources by context API reference
+    <https://cloudinary.com/documentation/admin_api#get_resources_by_context>`_
+
+    :param key:         Only assets with this context key are returned
+    :type key:          str
+    :param value:       Only assets with this value for the context key are returned
+    :type value:        str, optional
+    :param options:     Additional options
+    :type options:      dict, optional
+    :return:            Resources (assets) with a specified context key
+    :rtype:             Response
+    """
+    resource_type = options.pop("resource_type", "image")
+    uri = ["resources", resource_type, "context"]
+    params = only(options, "next_cursor", "max_results", "tags",
+                "context", "moderations", "direction", "metadata")
+    params["key"] = key
+    if value is not None:
+        params["value"] = value
+    return call_api("get", uri, params, **options)
+
+
 def resource(public_id, **options):
     resource_type = options.pop("resource_type", "image")
     upload_type = options.pop("type", "upload")
     uri = ["resources", resource_type, upload_type, public_id]
     params = only(options, "exif", "faces", "colors", "image_metadata", "cinemagraph_analysis",
-                  "pages", "phash", "coordinates", "max_results", "quality_analysis", "derived_next_cursor")
+                  "pages", "phash", "coordinates", "max_results", "quality_analysis", "derived_next_cursor",
+                  "accessibility_analysis", "versions")
     return call_api("get", uri, params, **options)
 
 
@@ -327,8 +355,8 @@ def restore(public_ids, **options):
     resource_type = options.pop("resource_type", "image")
     upload_type = options.pop("type", "upload")
     uri = ["resources", resource_type, upload_type, "restore"]
-    params = dict(public_ids=public_ids)
-    return call_api("post", uri, params, **options)
+    params = dict(public_ids=public_ids, **only(options, "versions"))
+    return call_json_api("post", uri, params, **options)
 
 
 def upload_mappings(**options):
@@ -390,90 +418,6 @@ def update_streaming_profile(name, **options):
     return call_api('PUT', uri, params, **options)
 
 
-def call_json_api(method, uri, jsonBody, **options):
-    logger.debug(jsonBody)
-    data = json.dumps(jsonBody).encode('utf-8')
-    return _call_api(method, uri, body=data,
-                     headers={'Content-Type': 'application/json'}, **options)
-
-
-def call_api(method, uri, params, **options):
-    return _call_api(method, uri, params=params, **options)
-
-
-def call_metadata_api(method, uri, params, **options):
-    """Private function that assists with performing an API call to the
-    metadata_fields part of the Admin API
-
-    :param method: The HTTP method. Valid methods: get, post, put, delete
-    :param uri: REST endpoint of the API (without 'metadata_fields')
-    :param params: Query/body parameters passed to the method
-    :param options: Additional options
-
-    :rtype: Response
-    """
-    uri = ["metadata_fields"] + (uri or [])
-    return call_json_api(method, uri, params, **options)
-
-
-def _call_api(method, uri, params=None, body=None, headers=None, **options):
-    prefix = options.pop("upload_prefix",
-                         cloudinary.config().upload_prefix) or "https://api.cloudinary.com"
-    cloud_name = options.pop("cloud_name", cloudinary.config().cloud_name)
-    if not cloud_name:
-        raise Exception("Must supply cloud_name")
-    api_key = options.pop("api_key", cloudinary.config().api_key)
-    if not api_key:
-        raise Exception("Must supply api_key")
-    api_secret = options.pop("api_secret", cloudinary.config().api_secret)
-    if not cloud_name:
-        raise Exception("Must supply api_secret")
-    api_url = "/".join([prefix, "v1_1", cloud_name] + uri)
-
-    processed_params = None
-    if isinstance(params, dict):
-        processed_params = {}
-        for key, value in params.items():
-            if isinstance(value, list) or isinstance(value, tuple):
-                value_list = {"{}[{}]".format(key, i): i_value for i, i_value in enumerate(value)}
-                processed_params.update(value_list)
-            elif value:
-                processed_params[key] = value
-
-    # Add authentication
-    req_headers = urllib3.make_headers(
-        basic_auth="{0}:{1}".format(api_key, api_secret),
-        user_agent=cloudinary.get_user_agent()
-    )
-    if headers is not None:
-        req_headers.update(headers)
-    kw = {}
-    if 'timeout' in options:
-        kw['timeout'] = options['timeout']
-    if body is not None:
-        kw['body'] = body
-    try:
-        response = _http.request(method.upper(), api_url, processed_params, req_headers, **kw)
-        body = response.data
-    except HTTPError as e:
-        raise GeneralError("Unexpected error {0}", e.message)
-    except socket.error as e:
-        raise GeneralError("Socket Error: %s" % (str(e)))
-
-    try:
-        result = json.loads(body.decode('utf-8'))
-    except Exception as e:
-        # Error is parsing json
-        raise GeneralError("Error parsing server response (%d) - %s. Got - %s" % (response.status, body, e))
-
-    if "error" in result:
-        exception_class = EXCEPTION_CODES.get(response.status) or Exception
-        exception_class = exception_class
-        raise exception_class("Error {0} - {1}".format(response.status, result["error"]["message"]))
-
-    return Response(result, response)
-
-
 def only(source, *keys):
     return {key: source[key] for key in keys if key in source}
 
diff --git a/lib/cloudinary/api_client/__init__.py b/lib/cloudinary/api_client/__init__.py
new file mode 100644
index 00000000..e69de29b
diff --git a/lib/cloudinary/api_client/call_account_api.py b/lib/cloudinary/api_client/call_account_api.py
new file mode 100644
index 00000000..c40aaf3b
--- /dev/null
+++ b/lib/cloudinary/api_client/call_account_api.py
@@ -0,0 +1,35 @@
+import cloudinary
+from cloudinary.api_client.execute_request import execute_request
+from cloudinary.provisioning.account_config import account_config
+from cloudinary.utils import get_http_connector
+
+
+PROVISIONING_SUB_PATH = "provisioning"
+ACCOUNT_SUB_PATH = "accounts"
+_http = get_http_connector(account_config(), cloudinary.CERT_KWARGS)
+
+
+def _call_account_api(method, uri, params=None, headers=None, **options):
+    prefix = options.pop("upload_prefix",
+                         cloudinary.config().upload_prefix) or "https://api.cloudinary.com"
+    account_id = options.pop("account_id", account_config().account_id)
+    if not account_id:
+        raise Exception("Must supply account_id")
+    provisioning_api_key = options.pop("provisioning_api_key", account_config().provisioning_api_key)
+    if not provisioning_api_key:
+        raise Exception("Must supply provisioning_api_key")
+    provisioning_api_secret = options.pop("provisioning_api_secret",
+                                          account_config().provisioning_api_secret)
+    if not provisioning_api_secret:
+        raise Exception("Must supply provisioning_api_secret")
+    provisioning_api_url = "/".join(
+        [prefix, cloudinary.API_VERSION, PROVISIONING_SUB_PATH, ACCOUNT_SUB_PATH, account_id] + uri)
+    auth = {"key": provisioning_api_key, "secret": provisioning_api_secret}
+
+    return execute_request(http_connector=_http,
+                           method=method,
+                           params=params,
+                           headers=headers,
+                           auth=auth,
+                           api_url=provisioning_api_url,
+                           **options)
diff --git a/lib/cloudinary/api_client/call_api.py b/lib/cloudinary/api_client/call_api.py
new file mode 100644
index 00000000..5b5eb4f5
--- /dev/null
+++ b/lib/cloudinary/api_client/call_api.py
@@ -0,0 +1,70 @@
+import json
+
+import cloudinary
+from cloudinary.api_client.execute_request import execute_request
+from cloudinary.utils import get_http_connector
+
+
+logger = cloudinary.logger
+_http = get_http_connector(cloudinary.config(), cloudinary.CERT_KWARGS)
+
+
+def call_metadata_api(method, uri, params, **options):
+    """Private function that assists with performing an API call to the
+    metadata_fields part of the Admin API
+    :param method: The HTTP method. Valid methods: get, post, put, delete
+    :param uri: REST endpoint of the API (without 'metadata_fields')
+    :param params: Query/body parameters passed to the method
+    :param options: Additional options
+    :rtype: Response
+    """
+    uri = ["metadata_fields"] + (uri or [])
+    return call_json_api(method, uri, params, **options)
+
+
+def call_json_api(method, uri, json_body, **options):
+    data = json.dumps(json_body).encode('utf-8')
+    return _call_api(method, uri, body=data, headers={'Content-Type': 'application/json'}, **options)
+
+
+def call_api(method, uri, params, **options):
+    return _call_api(method, uri, params=params, **options)
+
+
+def _call_api(method, uri, params=None, body=None, headers=None, **options):
+    prefix = options.pop("upload_prefix",
+                         cloudinary.config().upload_prefix) or "https://api.cloudinary.com"
+    cloud_name = options.pop("cloud_name", cloudinary.config().cloud_name)
+    if not cloud_name:
+        raise Exception("Must supply cloud_name")
+
+    api_key = options.pop("api_key", cloudinary.config().api_key)
+    api_secret = options.pop("api_secret", cloudinary.config().api_secret)
+    oauth_token = options.pop("oauth_token", cloudinary.config().oauth_token)
+
+    _validate_authorization(api_key, api_secret, oauth_token)
+
+    api_url = "/".join([prefix, cloudinary.API_VERSION, cloud_name] + uri)
+    auth = {"key": api_key, "secret": api_secret, "oauth_token": oauth_token}
+
+    if body is not None:
+        options["body"] = body
+
+    return execute_request(http_connector=_http,
+                           method=method,
+                           params=params,
+                           headers=headers,
+                           auth=auth,
+                           api_url=api_url,
+                           **options)
+
+
+def _validate_authorization(api_key, api_secret, oauth_token):
+    if oauth_token:
+        return
+
+    if not api_key:
+        raise Exception("Must supply api_key")
+
+    if not api_secret:
+        raise Exception("Must supply api_secret")
diff --git a/lib/cloudinary/api_client/execute_request.py b/lib/cloudinary/api_client/execute_request.py
new file mode 100644
index 00000000..4d6b8651
--- /dev/null
+++ b/lib/cloudinary/api_client/execute_request.py
@@ -0,0 +1,86 @@
+import email.utils
+import json
+import socket
+
+import urllib3
+from urllib3.exceptions import HTTPError
+
+import cloudinary
+from cloudinary.exceptions import (
+    BadRequest,
+    AuthorizationRequired,
+    NotAllowed,
+    NotFound,
+    AlreadyExists,
+    RateLimited,
+    GeneralError
+)
+from cloudinary.utils import process_params, safe_cast, smart_escape, unquote
+
+EXCEPTION_CODES = {
+    400: BadRequest,
+    401: AuthorizationRequired,
+    403: NotAllowed,
+    404: NotFound,
+    409: AlreadyExists,
+    420: RateLimited,
+    500: GeneralError
+}
+
+
+class Response(dict):
+    def __init__(self, result, response, **kwargs):
+        super(Response, self).__init__(**kwargs)
+        self.update(result)
+
+        self.rate_limit_allowed = safe_cast(response.headers.get("x-featureratelimit-limit"), int)
+        self.rate_limit_reset_at = safe_cast(response.headers.get("x-featureratelimit-reset"), email.utils.parsedate)
+        self.rate_limit_remaining = safe_cast(response.headers.get("x-featureratelimit-remaining"), int)
+
+
+def execute_request(http_connector, method, params, headers, auth, api_url, **options):
+    # authentication
+    key = auth.get("key")
+    secret = auth.get("secret")
+    oauth_token = auth.get("oauth_token")
+    req_headers = urllib3.make_headers(
+        user_agent=cloudinary.get_user_agent()
+    )
+    if oauth_token:
+        req_headers["authorization"] = "Bearer {}".format(oauth_token)
+    else:
+        req_headers.update(urllib3.make_headers(basic_auth="{0}:{1}".format(key, secret)))
+
+    if headers is not None:
+        req_headers.update(headers)
+
+    kw = {}
+    if "timeout" in options:
+        kw["timeout"] = options["timeout"]
+    if "body" in options:
+        kw["body"] = options["body"]
+
+    processed_params = process_params(params)
+
+    api_url = smart_escape(unquote(api_url))
+
+    try:
+        response = http_connector.request(method.upper(), api_url, processed_params, req_headers, **kw)
+        body = response.data
+    except HTTPError as e:
+        raise GeneralError("Unexpected error {0}", e.message)
+    except socket.error as e:
+        raise GeneralError("Socket Error: %s" % (str(e)))
+
+    try:
+        result = json.loads(body.decode('utf-8'))
+    except Exception as e:
+        # Error is parsing json
+        raise GeneralError("Error parsing server response (%d) - %s. Got - %s" % (response.status, body, e))
+
+    if "error" in result:
+        exception_class = EXCEPTION_CODES.get(response.status) or Exception
+        exception_class = exception_class
+        raise exception_class("Error {0} - {1}".format(response.status, result["error"]["message"]))
+
+    return Response(result, response)
diff --git a/lib/cloudinary/auth_token.py b/lib/cloudinary/auth_token.py
index 6ef3874c..3aaf3844 100644
--- a/lib/cloudinary/auth_token.py
+++ b/lib/cloudinary/auth_token.py
@@ -20,6 +20,9 @@ def generate(url=None, acl=None, start_time=None, duration=None,
         else:
             raise Exception("Must provide either expiration or duration")
 
+    if url is None and acl is None:
+        raise Exception("Must provide either acl or url")
+
     token_parts = []
     if ip is not None:
         token_parts.append("ip=" + ip)
diff --git a/lib/cloudinary/forms.py b/lib/cloudinary/forms.py
index ff83a98f..6c0ffaba 100644
--- a/lib/cloudinary/forms.py
+++ b/lib/cloudinary/forms.py
@@ -5,7 +5,7 @@ import cloudinary.uploader
 import cloudinary.utils
 from cloudinary import CloudinaryResource
 from django import forms
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 
 
 def cl_init_js_callbacks(form, request):
@@ -52,7 +52,7 @@ class CloudinaryInput(forms.TextInput):
 
 class CloudinaryJsFileField(forms.Field):
     default_error_messages = {
-        'required': _(u"No file selected!")
+        "required": _("No file selected!")
     }
 
     def __init__(self, attrs=None, options=None, autosave=True, *args, **kwargs):
@@ -121,7 +121,7 @@ class CloudinaryUnsignedJsFileField(CloudinaryJsFileField):
 
 class CloudinaryFileField(forms.FileField):
     my_default_error_messages = {
-        'required': _(u"No file selected!")
+        "required": _("No file selected!")
     }
     default_error_messages = forms.FileField.default_error_messages.copy()
     default_error_messages.update(my_default_error_messages)
diff --git a/lib/cloudinary/models.py b/lib/cloudinary/models.py
index a3c7591c..5ccb133d 100644
--- a/lib/cloudinary/models.py
+++ b/lib/cloudinary/models.py
@@ -107,6 +107,8 @@ class CloudinaryField(models.Field):
         if isinstance(value, UploadedFile):
             options = {"type": self.type, "resource_type": self.resource_type}
             options.update(self.options)
+            if hasattr(value, 'seekable') and value.seekable():
+                value.seek(0)
             instance_value = uploader.upload_resource(value, **options)
             setattr(model_instance, self.attname, instance_value)
             if self.width_field:
diff --git a/lib/cloudinary/provisioning/__init__.py b/lib/cloudinary/provisioning/__init__.py
new file mode 100644
index 00000000..09afc114
--- /dev/null
+++ b/lib/cloudinary/provisioning/__init__.py
@@ -0,0 +1,5 @@
+from .account_config import AccountConfig, account_config, reset_config
+from .account import (sub_accounts, create_sub_account, delete_sub_account, sub_account, update_sub_account,
+                      user_groups, create_user_group, update_user_group, delete_user_group, user_group,
+                      add_user_to_group, remove_user_from_group, user_group_users, user_in_user_groups,
+                      users, create_user, delete_user, user, update_user, Role)
diff --git a/lib/cloudinary/provisioning/account.py b/lib/cloudinary/provisioning/account.py
new file mode 100644
index 00000000..9dc97cf1
--- /dev/null
+++ b/lib/cloudinary/provisioning/account.py
@@ -0,0 +1,366 @@
+from cloudinary.api_client.call_account_api import _call_account_api
+from cloudinary.utils import encode_list
+
+
+SUB_ACCOUNTS_SUB_PATH = "sub_accounts"
+USERS_SUB_PATH = "users"
+USER_GROUPS_SUB_PATH = "user_groups"
+
+
+class Role(object):
+    """
+    A user role to use in the user management API (create/update user).
+    """
+    MASTER_ADMIN = "master_admin"
+    ADMIN = "admin"
+    BILLING = "billing"
+    TECHNICAL_ADMIN = "technical_admin"
+    REPORTS = "reports"
+    MEDIA_LIBRARY_ADMIN = "media_library_admin"
+    MEDIA_LIBRARY_USER = "media_library_user"
+
+
+def sub_accounts(enabled=None, ids=None, prefix=None, **options):
+    """
+    List all sub accounts
+    :param enabled:     Whether to only return enabled sub-accounts (true) or disabled accounts (false).
+                        Default: all accounts are returned (both enabled and disabled).
+    :type enabled:      bool, optional
+    :param ids:         List of sub-account IDs. Up to 100. When provided, other filters are ignored.
+    :type ids:          list, optional
+    :param prefix:      Search by prefix of the sub-account name. Case-insensitive.
+    :type prefix:       str, optional
+    :param options:     Generic advanced options dict, see online documentation
+    :type options:      dict, optional
+    :return:            A list of sub accounts
+    :rtype:             dict
+    """
+    uri = [SUB_ACCOUNTS_SUB_PATH]
+    params = {"ids": ids, "enabled": enabled, "prefix": prefix}
+    return _call_account_api("GET", uri, params=params, **options)
+
+
+def create_sub_account(name, cloud_name=None, custom_attributes=None, enabled=None,
+                       base_account=None, **options):
+    """
+    Create a new sub account
+    :param name:                Name of the new sub account
+    :type name:                 str
+    :param cloud_name:          A case-insensitive cloud name comprised of alphanumeric and underscore characters.
+                                * Generates an error if the cloud name is not unique across all Cloudinary accounts.
+    :type cloud_name:           str, optional
+    :param custom_attributes:   Any custom attributes you want to associate with the sub-account
+    :type custom_attributes:    dict, optional
+    :param enabled:             Whether to create the account as enabled (default is enabled).
+    :type enabled:              bool, optional
+    :param base_account:        ID of sub-account from which to copy settings
+    :type base_account:         str, optional
+    :param options:             Generic advanced options dict, see online documentation
+    :type options:              dict, optional
+    :return:                    The created sub account
+    :rtype:                     dict
+    """
+    uri = [SUB_ACCOUNTS_SUB_PATH]
+    params = {"name": name,
+              "cloud_name": cloud_name,
+              "custom_attributes": custom_attributes,
+              "enabled": enabled,
+              "base_account": base_account}
+    return _call_account_api("POST", uri, params=params, **options)
+
+
+def delete_sub_account(sub_account_id, **options):
+    """
+    Delete a sub account
+    :param sub_account_id:      The id of the sub account
+    :type sub_account_id:       str
+    :param options:             Generic advanced options dict, see online documentation
+    :type options:              dict, optional
+    :return:                    Result message
+    :rtype:                     dict
+    """
+    uri = [SUB_ACCOUNTS_SUB_PATH, sub_account_id]
+    return _call_account_api("delete", uri, {}, **options)
+
+
+def sub_account(sub_account_id, **options):
+    """
+    Get information of a sub account
+    :param sub_account_id:      The id of the sub account
+    :type sub_account_id:       str
+    :param options:             Generic advanced options dict, see online documentation
+    :type options:              dict, optional
+    :return:                    A sub account
+    :rtype:                     dict
+    """
+    uri = [SUB_ACCOUNTS_SUB_PATH, sub_account_id]
+    return _call_account_api("get", uri, {}, **options)
+
+
+def update_sub_account(sub_account_id, name=None, cloud_name=None, custom_attributes=None,
+                       enabled=None, base_account=None,
+                       **options):
+    """
+    Update a sub account
+    :param sub_account_id:      The id of the sub account
+    :type sub_account_id:       str
+    :param name:                Name of the account
+    :type name:                 str, optional
+    :param cloud_name:          Unique cloud name
+    :type cloud_name:           str, optional
+    :param custom_attributes:   Any custom attributes you want to associate with the sub-account.
+    :type custom_attributes:    dict, optional
+    :param enabled:             Whether to create the account as enabled (default is enabled).
+    :type enabled:              bool, optional
+    :param base_account:        ID of sub-account from which to copy settings
+    :type base_account:         str, optional
+    :param options:             Generic advanced options dict, see online documentation
+    :type options:              dict, optional
+    :return:                    Updated sub account
+    :rtype:                     dict
+    """
+    uri = [SUB_ACCOUNTS_SUB_PATH, sub_account_id]
+    params = {"name": name,
+              "cloud_name": cloud_name,
+              "custom_attributes": custom_attributes,
+              "enabled": enabled,
+              "base_account": base_account}
+    return _call_account_api("put", uri, params=params, **options)
+
+
+def users(user_ids=None, sub_account_id=None, pending=None, prefix=None, **options):
+    """
+    List all users
+    :param user_ids:        The ids of the users to fetch
+    :type user_ids:         list, optional
+    :param sub_account_id:  The id of a sub account
+    :type sub_account_id:   str, optional
+    :param pending:         Limit results to pending users (True),
+                            users that are not pending (False),
+                            or all users (None, the default).
+    :type pending:          bool, optional
+    :param prefix:          User prefix
+    :type prefix:           str, optional
+    :param options:         Generic advanced options dict, see online documentation.
+    :type options:          dict, optional
+    :return:                List of users associated with the account
+    :rtype:                 dict
+    """
+    uri = [USERS_SUB_PATH]
+    user_ids = encode_list(user_ids)
+    params = {"ids": user_ids,
+              "sub_account_id": sub_account_id,
+              "pending": pending,
+              "prefix": prefix}
+    return _call_account_api("get", uri, params=params, **options)
+
+
+def create_user(name, email, role, sub_account_ids=None, **options):
+    """
+    Create a user
+    :param name:                Username
+    :type name:                 str
+    :param email:               User's email
+    :type email:                str
+    :param role:                User's role
+    :type role:                 str
+    :param sub_account_ids:     Optional. Sub accounts to associate with the user
+    :type sub_account_ids:      list, optional
+    :param options:             Generic advanced options dict, see online documentation.
+    :type options:              dict, optional
+    :return:                    Details of created user
+    :rtype:                     dict
+    """
+    uri = [USERS_SUB_PATH]
+    params = {"name": name,
+              "email": email,
+              "role": role,
+              "sub_account_ids": sub_account_ids}
+    return _call_account_api("post", uri, params=params, **options)
+
+
+def delete_user(user_id, **options):
+    """
+    Delete a user
+    :param user_id:             The id of user to delete
+    :type user_id:              str
+    :param options:             Generic advanced options dict, see online documentation.
+    :type options:              dict, optional
+    :return:                    Result message
+    :rtype:                     dict
+    """
+    uri = [USERS_SUB_PATH, user_id]
+    return _call_account_api("delete", uri, {}, **options)
+
+
+def user(user_id, **options):
+    """
+    Get information of a user
+    :param user_id:             The id of the user
+    :type user_id:              str
+    :param options:             Generic advanced options dict, see online documentation.
+    :type options:              dict, optional
+    :return:                    A user
+    :rtype:                     dict
+    """
+    uri = [USERS_SUB_PATH, user_id]
+    return _call_account_api("get", uri, {}, **options)
+
+
+def update_user(user_id, name=None, email=None, role=None, sub_account_ids=None, **options):
+    """
+    Update a user
+    :param user_id:             The id of the user to update
+    :type user_id:              str
+    :param name:                Username
+    :type name:                 str, optional
+    :param email:               User's email
+    :type email:                str, optional
+    :param role:                User's role
+    :type role:                 Role, optional
+    :param sub_account_ids:     The list of sub-account IDs that this user can access.
+                                Note: This parameter is ignored if the role is specified as master_admin.
+    :type sub_account_ids:      list, optional
+    :param options:             Generic advanced options dict, see online documentation.
+    :type options:              dict, optional
+    :return:                    The updated user
+    :rtype:                     dict
+    """
+    uri = [USERS_SUB_PATH, user_id]
+    params = {"name": name,
+              "email": email,
+              "role": role,
+              "sub_account_ids": sub_account_ids}
+    return _call_account_api("put", uri, params=params, **options)
+
+
+def user_groups(**options):
+    """
+    List all user groups
+    :param options:         Generic advanced options dict, see online documentation
+    :type options:          dict, optional
+    :return:                List of user groups
+    :rtype:                 ProvisioningAPIRespose
+    """
+    uri = [USER_GROUPS_SUB_PATH]
+    return _call_account_api("get", uri, {}, **options)
+
+
+def create_user_group(name, **options):
+    """
+    Create a new user group
+    :param name:            Name of the user group
+    :type name:             str
+    :param options:         Generic advanced options dict, see online documentation
+    :type options:          dict, optional
+    :return:                The newly created group
+    :rtype:                 dict
+    """
+    uri = [USER_GROUPS_SUB_PATH]
+    params = {"name": name}
+    return _call_account_api("post", uri, params, **options)
+
+
+def update_user_group(user_group_id, name, **options):
+    """
+    Update a user group
+    :param user_group_id:       The id of the user group to update
+    :type user_group_id:        str
+    :param name:                Name of the user group
+    :type name:                 str, optional
+    :param options:             Generic advanced options dict, see online documentation
+    :type options:              dict, optional
+    :return:                    The updated group
+    :rtype:                     dict
+    """
+    uri = [USER_GROUPS_SUB_PATH, user_group_id]
+    params = {"name": name}
+    return _call_account_api("put", uri, params, **options)
+
+
+def delete_user_group(user_group_id, **options):
+    """
+    Delete a user group
+    :param user_group_id:       The id of the user group to delete
+    :type user_group_id:        str
+    :param options:             Generic advanced options dict, see online documentation
+    :type options:              dict, optional
+    :return:                    The result message
+    :rtype:                     dict
+    """
+    uri = [USER_GROUPS_SUB_PATH, user_group_id]
+    return _call_account_api("delete", uri, {}, **options)
+
+
+def user_group(user_group_id, **options):
+    """
+    Get information of a user group
+    :param user_group_id:       The id of the user group
+    :type user_group_id:        str
+    :param options:             Generic advanced options dict, see online documentation
+    :type options:              dict, optional
+    :return:                    Details of the group
+    :rtype:                     dict
+    """
+    uri = [USER_GROUPS_SUB_PATH, user_group_id]
+    return _call_account_api("get", uri, {}, **options)
+
+
+def add_user_to_group(user_group_id, user_id, **options):
+    """
+    Add a user to a user group
+    :param user_group_id:       The id of the user group to add the user to
+    :type user_group_id:        str
+    :param user_id:             The user id to add
+    :type user_id:              str
+    :param options:             Generic advanced options dict, see online documentation
+    :type options:              dict, optional
+    :return:                    List of users in the group
+    :rtype:                     dict
+    """
+    uri = [USER_GROUPS_SUB_PATH, user_group_id, "users", user_id]
+    return _call_account_api("post", uri, {}, **options)
+
+
+def remove_user_from_group(user_group_id, user_id, **options):
+    """
+    Remove a user from a user group
+    :param user_group_id:       The id of the user group to remove the user from
+    :type user_group_id:        str
+    :param user_id:             The id of the user to remove
+    :type user_id:              str
+    :param options:             Generic advanced options dict, see online documentation
+    :type options:              dict, optional
+    :return:                    List of users in the group
+    :rtype:                     dict
+    """
+    uri = [USER_GROUPS_SUB_PATH, user_group_id, "users", user_id]
+    return _call_account_api("delete", uri, {}, **options)
+
+
+def user_group_users(user_group_id, **options):
+    """
+    Get all users in a user group
+    :param user_group_id:       The id of user group to get list of users
+    :type user_group_id:        str
+    :param options:             Generic advanced options dict, see online documentation
+    :type options:              dict, optional
+    :return:                    List of users in the group
+    :rtype:                     dict
+    """
+    uri = [USER_GROUPS_SUB_PATH, user_group_id, "users"]
+    return _call_account_api("get", uri, {}, **options)
+
+
+def user_in_user_groups(user_id, **options):
+    """
+    Get all user groups a user belongs to
+    :param user_id:             The id of user
+    :param user_id:             str
+    :param options:             Generic advanced options dict, see online documentation
+    :type options:              dict, optional
+    :return:                    List of groups user is in
+    :rtype:                     dict
+    """
+    uri = [USER_GROUPS_SUB_PATH, user_id]
+    return _call_account_api("get", uri, {}, **options)
diff --git a/lib/cloudinary/provisioning/account_config.py b/lib/cloudinary/provisioning/account_config.py
new file mode 100644
index 00000000..0448e60a
--- /dev/null
+++ b/lib/cloudinary/provisioning/account_config.py
@@ -0,0 +1,42 @@
+from __future__ import absolute_import
+
+import os
+
+from cloudinary import BaseConfig, import_django_settings
+
+ACCOUNT_URI_SCHEME = "account"
+
+
+class AccountConfig(BaseConfig):
+    def __init__(self):
+        self._uri_scheme = ACCOUNT_URI_SCHEME
+
+        super(AccountConfig, self).__init__()
+
+    def _config_from_parsed_url(self, parsed_url):
+        if not self._is_url_scheme_valid(parsed_url):
+            raise ValueError("Invalid CLOUDINARY_ACCOUNT_URL scheme. URL should begin with 'account://'")
+
+        return {
+            "account_id": parsed_url.hostname,
+            "provisioning_api_key": parsed_url.username,
+            "provisioning_api_secret": parsed_url.password,
+        }
+
+    def _load_config_from_env(self):
+        if os.environ.get("CLOUDINARY_ACCOUNT_URL"):
+            self._load_from_url(os.environ.get("CLOUDINARY_ACCOUNT_URL"))
+
+
+def account_config(**keywords):
+    global _account_config
+    _account_config.update(**keywords)
+    return _account_config
+
+
+def reset_config():
+    global _account_config
+    _account_config = AccountConfig()
+
+
+_account_config = AccountConfig()
diff --git a/lib/cloudinary/search.py b/lib/cloudinary/search.py
index e3a52b49..0b65d3b9 100644
--- a/lib/cloudinary/search.py
+++ b/lib/cloudinary/search.py
@@ -1,7 +1,7 @@
 import json
 from copy import deepcopy
 
-from cloudinary.api import call_json_api
+from cloudinary.api_client.call_api import call_json_api
 
 
 class Search:
diff --git a/lib/cloudinary/static/js/jquery.cloudinary.js b/lib/cloudinary/static/js/jquery.cloudinary.js
index 9def7cf7..cbe7eaff 100644
--- a/lib/cloudinary/static/js/jquery.cloudinary.js
+++ b/lib/cloudinary/static/js/jquery.cloudinary.js
@@ -164,7 +164,7 @@ var slice = [].slice,
   * @returns {boolean} Returns `true` if `value` is correctly classified, else `false`.
   * @example
   *
-  * function Foo(){};  
+  * function Foo(){};
   * isFunction(Foo);
   * // => true
   *
@@ -1403,7 +1403,8 @@ var slice = [].slice,
       "*": "mul",
       "/": "div",
       "+": "add",
-      "-": "sub"
+      "-": "sub",
+      "^": "pow",
     };
 
 
@@ -1472,30 +1473,37 @@ var slice = [].slice,
       return new this(expressionStr);
     };
 
-
     /**
      * Normalize a string expression
      * @function Cloudinary#normalize
      * @param {string} expression a expression, e.g. "w gt 100", "width_gt_100", "width > 100"
      * @return {string} the normalized form of the value expression, e.g. "w_gt_100"
      */
-
     Expression.normalize = function(expression) {
-      var operators, pattern, replaceRE;
+      var operators, operatorsPattern, operatorsReplaceRE, predefinedVarsPattern, predefinedVarsReplaceRE;
       if (expression == null) {
         return expression;
       }
       expression = String(expression);
-      operators = "\\|\\||>=|<=|&&|!=|>|=|<|/|-|\\+|\\*";
-      pattern = "((" + operators + ")(?=[ _])|" + Object.keys(Expression.PREDEFINED_VARS).join("|") + ")";
-      replaceRE = new RegExp(pattern, "g");
-      expression = expression.replace(replaceRE, function(match) {
-        return Expression.OPERATORS[match] || Expression.PREDEFINED_VARS[match];
+      operators = "\\|\\||>=|<=|&&|!=|>|=|<|/|-|\\+|\\*|\\^";
+
+      // operators
+      operatorsPattern = "((" + operators + ")(?=[ _]))";
+      operatorsReplaceRE = new RegExp(operatorsPattern, "g");
+      expression = expression.replace(operatorsReplaceRE, function (match) {
+        return Expression.OPERATORS[match];
       });
+
+      // predefined variables
+      predefinedVarsPattern = "(" + Object.keys(Expression.PREDEFINED_VARS).join("|") + ")";
+      predefinedVarsReplaceRE = new RegExp(predefinedVarsPattern, "g");
+      expression = expression.replace(predefinedVarsReplaceRE, function(match, p1, offset){
+        return (expression[offset - 1] === '$' ? match : Expression.PREDEFINED_VARS[match]);
+      });
+
       return expression.replace(/[ _]+/g, '_');
     };
 
-
     /**
      * Serialize the expression
      * @return {string} the expression as a string
@@ -3070,7 +3078,7 @@ var slice = [].slice,
      * @protected
      * @param {string} key - attribute name
      * @param {*|boolean} value - the value of the attribute. If the value is boolean `true`, return the key only.
-     * @returns {string} the attribute  
+     * @returns {string} the attribute
      *
      */
 
@@ -4294,12 +4302,20 @@ var slice = [].slice,
               switch (false) {
                 case !/w_auto:breakpoints/.test(dataSrc):
                   requiredWidth = maxWidth(containerWidth, tag);
-                  dataSrc = dataSrc.replace(/w_auto:breakpoints([_0-9]*)(:[0-9]+)?/, "w_auto:breakpoints$1:" + requiredWidth);
+                  if (requiredWidth) {
+                    dataSrc = dataSrc.replace(/w_auto:breakpoints([_0-9]*)(:[0-9]+)?/, "w_auto:breakpoints$1:" + requiredWidth);
+                  } else {
+                    setUrl = false;
+                  }
                   break;
                 case !(match = /w_auto(:(\d+))?/.exec(dataSrc)):
                   requiredWidth = applyBreakpoints.call(this, tag, containerWidth, match[2], options);
                   requiredWidth = maxWidth(requiredWidth, tag);
-                  dataSrc = dataSrc.replace(/w_auto[^,\/]*/g, "w_" + requiredWidth);
+                  if (requiredWidth) {
+                    dataSrc = dataSrc.replace(/w_auto[^,\/]*/g, "w_" + requiredWidth);
+                  } else {
+                    setUrl = false;
+                  }
               }
               Util.removeAttribute(tag, 'width');
               if (!options.responsive_preserve_height) {
diff --git a/lib/cloudinary/templates/cloudinary_includes.html b/lib/cloudinary/templates/cloudinary_includes.html
index 6300c037..82361c33 100644
--- a/lib/cloudinary/templates/cloudinary_includes.html
+++ b/lib/cloudinary/templates/cloudinary_includes.html
@@ -1,4 +1,4 @@
-{% load staticfiles %}
+{% load static %}
 
 <script src="{% static "js/jquery.ui.widget.js" %}" type="text/javascript"></script>
 <script src="{% static "js/jquery.iframe-transport.js" %}" type="text/javascript"></script>
diff --git a/lib/cloudinary/uploader.py b/lib/cloudinary/uploader.py
index a396645c..9ee1c77d 100644
--- a/lib/cloudinary/uploader.py
+++ b/lib/cloudinary/uploader.py
@@ -58,7 +58,7 @@ def upload_image(file, **options):
 
 
 def upload_resource(file, **options):
-    result = upload(file, **options)
+    result = upload_large(file, **options)
     return cloudinary.CloudinaryResource(
         result["public_id"], version=str(result["version"]),
         format=result.get("format"), type=result["type"],
@@ -131,7 +131,9 @@ def rename(from_public_id, to_public_id, **options):
         "invalidate": options.get("invalidate"),
         "from_public_id": from_public_id,
         "to_public_id": to_public_id,
-        "to_type": options.get("to_type")
+        "to_type": options.get("to_type"),
+        "context": options.get("context"),
+        "metadata": options.get("metadata")
     }
     return call_api("rename", params, **options)
 
@@ -180,30 +182,81 @@ def create_zip(**options):
     return create_archive(target_format="zip", **options)
 
 
-def generate_sprite(tag, **options):
-    params = {
-        "timestamp": utils.now(),
-        "tag": tag,
-        "async": options.get("async"),
-        "notification_url": options.get("notification_url"),
-        "transformation": utils.generate_transformation_string(
-            fetch_format=options.get("format"), **options)[0]
-    }
+def generate_sprite(tag=None, urls=None, **options):
+    """
+    Generates sprites by merging multiple images into a single large image.
+
+    See: `Sprite method API reference
+    <https://cloudinary.com/documentation/image_upload_api_reference#sprite_method>`_
+
+    :param tag:     The sprite is created from all images with this tag. If not set - `urls` parameter is required
+    :type tag:      str
+    :param urls:    List of URLs to create a sprite from. Can only be used if `tag` is not set
+    :type urls:     list
+    :param options: Additional options
+    :type options:  dict, optional
+    :return:        Dictionary with meta information URLs of generated sprite resources
+    :rtype:         dict
+    """
+    params = utils.build_multi_and_sprite_params(tag=tag, urls=urls, **options)
     return call_api("sprite", params, **options)
 
 
-def multi(tag, **options):
-    params = {
-        "timestamp": utils.now(),
-        "tag": tag,
-        "format": options.get("format"),
-        "async": options.get("async"),
-        "notification_url": options.get("notification_url"),
-        "transformation": utils.generate_transformation_string(**options)[0]
-    }
+def download_generated_sprite(tag=None, urls=None, **options):
+    """
+    Returns signed URL for the sprite endpoint with `mode=download`
+
+    :param tag:     The sprite is created from all images with this tag. If not set - `urls` parameter is required
+    :type tag:      str
+    :param urls:    List of URLs to create a sprite from. Can only be used if `tag` is not set
+    :type urls:     list
+    :param options: Additional options
+    :type options:  dict, optional
+    :return:        The signed URL to download sprite
+    :rtype:         str
+    """
+    params = utils.build_multi_and_sprite_params(tag=tag, urls=urls, **options)
+    return utils.cloudinary_api_download_url(action="sprite", params=params, **options)
+
+
+def multi(tag=None, urls=None, **options):
+    """
+    Creates either a single animated image, video or a PDF.
+
+    See: `Upload method API reference
+    <https://cloudinary.com/documentation/image_upload_api_reference#multi_method>`_
+
+    :param tag:     The animated image, video or PDF is created from all images with this tag.
+                    If not set - `urls` parameter is required
+    :type tag:      str
+    :param urls:    List of URLs to create an animated image, video or PDF from. Can only be used if `tag` is not set
+    :type urls:     list
+    :param options: Additional options
+    :type options:  dict, optional
+    :return:        Dictionary with meta information URLs of the generated file
+    :rtype:         dict
+    """
+    params = utils.build_multi_and_sprite_params(tag=tag, urls=urls, **options)
     return call_api("multi", params, **options)
 
 
+def download_multi(tag=None, urls=None, **options):
+    """
+    Returns signed URL for the multi endpoint with `mode=download`
+
+    :param tag:     The sprite is created from all images with this tag. If not set - `urls` parameter is required
+    :type tag:      str
+    :param urls:    List of URLs to create a sprite from. Can only be used if `tag` is not set
+    :type urls:     list
+    :param options: Additional options
+    :type options:  dict, optional
+    :return:        The signed URL to download multi
+    :rtype:         str
+    """
+    params = utils.build_multi_and_sprite_params(tag=tag, urls=urls, **options)
+    return utils.cloudinary_api_download_url(action="multi", params=params, **options)
+
+
 def explode(public_id, **options):
     params = {
         "timestamp": utils.now(),
@@ -347,80 +400,80 @@ def call_cacheable_api(action, params, http_headers=None, return_error=False, un
 
 
 def call_api(action, params, http_headers=None, return_error=False, unsigned=False, file=None, timeout=None, **options):
-    if http_headers is None:
-        http_headers = {}
-    file_io = None
-    try:
-        if unsigned:
-            params = utils.cleanup_params(params)
-        else:
-            params = utils.sign_request(params, options)
+    params = utils.cleanup_params(params)
 
-        param_list = OrderedDict()
-        for k, v in params.items():
-            if isinstance(v, list):
-                for i in range(len(v)):
-                    param_list["{0}[{1}]".format(k, i)] = v[i]
-            elif v:
-                param_list[k] = v
+    headers = {"User-Agent": cloudinary.get_user_agent()}
 
-        api_url = utils.cloudinary_api_url(action, **options)
-        if file:
-            filename = options.get("filename")  # Custom filename provided by user (relevant only for streams and files)
-
-            if isinstance(file, string_types):
-                if utils.is_remote_url(file):
-                    # URL
-                    name = None
-                    data = file
-                else:
-                    # file path
-                    name = filename or file
-                    with open(file, "rb") as opened:
-                        data = opened.read()
-            elif hasattr(file, 'read') and callable(file.read):
-                # stream
-                data = file.read()
-                name = filename or (file.name if hasattr(file, 'name') and isinstance(file.name, str) else "stream")
-            elif isinstance(file, tuple):
-                name, data = file
-            else:
-                # Not a string, not a stream
-                name = filename or "file"
-                data = file
-
-            param_list["file"] = (name, data) if name else data
-
-        headers = {"User-Agent": cloudinary.get_user_agent()}
+    if http_headers is not None:
         headers.update(http_headers)
 
-        kw = {}
-        if timeout is not None:
-            kw['timeout'] = timeout
+    oauth_token = options.get("oauth_token", cloudinary.config().oauth_token)
 
-        code = 200
-        try:
-            response = _http.request("POST", api_url, param_list, headers, **kw)
-        except HTTPError as e:
-            raise Error("Unexpected error - {0!r}".format(e))
-        except socket.error as e:
-            raise Error("Socket error: {0!r}".format(e))
+    if oauth_token:
+        headers["authorization"] = "Bearer {}".format(oauth_token)
+    elif not unsigned:
+        params = utils.sign_request(params, options)
 
-        try:
-            result = json.loads(response.data.decode('utf-8'))
-        except Exception as e:
-            # Error is parsing json
-            raise Error("Error parsing server response (%d) - %s. Got - %s" % (response.status, response.data, e))
+    param_list = []
+    for k, v in params.items():
+        if isinstance(v, list):
+            for i in v:
+                param_list.append(("{0}[]".format(k), i))
+        elif v:
+            param_list.append((k, v))
 
-        if "error" in result:
-            if response.status not in [200, 400, 401, 403, 404, 500]:
-                code = response.status
-            if return_error:
-                result["error"]["http_code"] = code
+    api_url = utils.cloudinary_api_url(action, **options)
+
+    if file:
+        filename = options.get("filename")  # Custom filename provided by user (relevant only for streams and files)
+
+        if isinstance(file, string_types):
+            if utils.is_remote_url(file):
+                # URL
+                name = None
+                data = file
             else:
-                raise Error(result["error"]["message"])
+                # file path
+                name = filename or file
+                with open(file, "rb") as opened:
+                    data = opened.read()
+        elif hasattr(file, 'read') and callable(file.read):
+            # stream
+            data = file.read()
+            name = filename or (file.name if hasattr(file, 'name') and isinstance(file.name, str) else "stream")
+        elif isinstance(file, tuple):
+            name, data = file
+        else:
+            # Not a string, not a stream
+            name = filename or "file"
+            data = file
 
-        return result
-    finally:
-        if file_io:
-            file_io.close()
+        param_list.append(("file", (name, data) if name else data))
+
+    kw = {}
+    if timeout is not None:
+        kw['timeout'] = timeout
+
+    code = 200
+    try:
+        response = _http.request("POST", api_url, param_list, headers, **kw)
+    except HTTPError as e:
+        raise Error("Unexpected error - {0!r}".format(e))
+    except socket.error as e:
+        raise Error("Socket error: {0!r}".format(e))
+
+    try:
+        result = json.loads(response.data.decode('utf-8'))
+    except Exception as e:
+        # Error is parsing json
+        raise Error("Error parsing server response (%d) - %s. Got - %s" % (response.status, response.data, e))
+
+    if "error" in result:
+        if response.status not in [200, 400, 401, 403, 404, 500]:
+            code = response.status
+        if return_error:
+            result["error"]["http_code"] = code
+        else:
+            raise Error(result["error"]["message"])
+
+    return result
diff --git a/lib/cloudinary/utils.py b/lib/cloudinary/utils.py
index 872a7588..276a0a7d 100644
--- a/lib/cloudinary/utils.py
+++ b/lib/cloudinary/utils.py
@@ -15,10 +15,10 @@ from collections import OrderedDict
 from datetime import datetime, date
 from fractions import Fraction
 from numbers import Number
-from urllib3 import ProxyManager, PoolManager
 
 import six.moves.urllib.parse
-from six import iteritems
+from six import iteritems, string_types
+from urllib3 import ProxyManager, PoolManager
 
 import cloudinary
 from cloudinary import auth_token
@@ -37,7 +37,7 @@ DEFAULT_RESPONSIVE_WIDTH_TRANSFORMATION = {"width": "auto", "crop": "limit"}
 RANGE_VALUE_RE = r'^(?P<value>(\d+\.)?\d+)(?P<modifier>[%pP])?$'
 RANGE_RE = r'^(\d+\.)?\d+[%pP]?\.\.(\d+\.)?\d+[%pP]?$'
 FLOAT_RE = r'^(\d+)\.(\d+)?$'
-REMOTE_URL_RE = r'ftp:|https?:|s3:|gs:|data:([\w-]+\/[\w-]+)?(;[\w-]+=[\w-]+)*;base64,([a-zA-Z0-9\/+\n=]+)$'
+REMOTE_URL_RE = r'ftp:|https?:|s3:|gs:|data:([\w-]+\/[\w-]+(\+[\w-]+)?)?(;[\w-]+=[\w-]+)*;base64,([a-zA-Z0-9\/+\n=]+)$'
 __LAYER_KEYWORD_PARAMS = [("font_weight", "normal"),
                           ("font_style", "normal"),
                           ("text_decoration", "none"),
@@ -63,7 +63,9 @@ __URL_KEYS = [
     'type',
     'url_suffix',
     'use_root_path',
-    'version'
+    'version',
+    'long_url_signature',
+    'signature_algorithm',
 ]
 
 __SIMPLE_UPLOAD_PARAMS = [
@@ -79,10 +81,12 @@ __SIMPLE_UPLOAD_PARAMS = [
     "use_filename",
     "unique_filename",
     "discard_original_filename",
+    "filename_override",
     "invalidate",
     "notification_url",
     "eager_notification_url",
     "eager_async",
+    "eval",
     "proxy",
     "folder",
     "overwrite",
@@ -101,6 +105,7 @@ __SIMPLE_UPLOAD_PARAMS = [
     "auto_tagging",
     "async",
     "cinemagraph_analysis",
+    "accessibility_analysis",
 ]
 
 __SERIALIZED_UPLOAD_PARAMS = [
@@ -121,16 +126,32 @@ __SERIALIZED_UPLOAD_PARAMS = [
 
 upload_params = __SIMPLE_UPLOAD_PARAMS + __SERIALIZED_UPLOAD_PARAMS
 
+SHORT_URL_SIGNATURE_LENGTH = 8
+LONG_URL_SIGNATURE_LENGTH = 32
 
-def compute_hex_hash(s):
+SIGNATURE_SHA1 = "sha1"
+SIGNATURE_SHA256 = "sha256"
+
+signature_algorithms = {
+    SIGNATURE_SHA1: hashlib.sha1,
+    SIGNATURE_SHA256: hashlib.sha256,
+}
+
+
+def compute_hex_hash(s, algorithm=SIGNATURE_SHA1):
     """
-    Compute hash and convert the result to HEX string
+    Computes string hash using specified algorithm and return HEX string representation of hash.
 
-    :param s: string to process
+    :param s:         String to compute hash for
+    :param algorithm: The name of algorithm to use for computing hash
 
-    :return: HEX string
+    :return: HEX string of computed hash value
     """
-    return hashlib.sha1(to_bytes(s)).hexdigest()
+    try:
+        hash_fn = signature_algorithms[algorithm]
+    except KeyError:
+        raise ValueError('Unsupported hash algorithm: {}'.format(algorithm))
+    return hash_fn(to_bytes(s)).hexdigest()
 
 
 def build_array(arg):
@@ -189,7 +210,7 @@ def encode_double_array(array):
     if len(array) > 0 and isinstance(array[0], list):
         return "|".join([",".join([str(i) for i in build_array(inner)]) for inner in array])
     else:
-        return ",".join([str(i) for i in array])
+        return encode_list([str(i) for i in array])
 
 
 def encode_dict(arg):
@@ -203,16 +224,37 @@ def encode_dict(arg):
         return arg
 
 
-def encode_context(context):
+def normalize_context_value(value):
     """
-       :param context: dict of context to be encoded
-       :return: a joined string of all keys and values properly escaped and separated by a pipe character
+    Escape "=" and "|" delimiter characters and json encode lists
+
+    :param value: Value to escape
+    :type value: int or str or list or tuple
+
+    :return: The normalized value
+    :rtype: str
     """
 
+    if isinstance(value, (list, tuple)):
+        value = json_encode(value)
+
+    return str(value).replace("=", "\\=").replace("|", "\\|")
+
+
+def encode_context(context):
+    """
+    Encode metadata fields based on incoming value.
+
+    List and tuple values are encoded to json strings.
+
+    :param context: dict of context to be encoded
+
+    :return: a joined string of all keys and values properly escaped and separated by a pipe character
+    """
     if not isinstance(context, dict):
         return context
 
-    return "|".join(("{}={}".format(k, v.replace("=", "\\=").replace("|", "\\|"))) for k, v in iteritems(context))
+    return "|".join(("{}={}".format(k, normalize_context_value(v))) for k, v in iteritems(context))
 
 
 def json_encode(value):
@@ -226,6 +268,17 @@ def json_encode(value):
     return json.dumps(value, default=__json_serializer, separators=(',', ':'))
 
 
+def encode_date_to_usage_api_format(date_obj):
+    """
+    Encodes date object to `dd-mm-yyyy` format string
+
+    :param date_obj: datetime.date object to encode
+
+    :return: Encoded date as a string
+    """
+    return date_obj.strftime('%d-%m-%Y')
+
+
 def patch_fetch_format(options):
     """
     When upload type is fetch, remove the format options.
@@ -488,6 +541,19 @@ def process_radius(param):
     return str(param)
 
 
+def process_params(params):
+    processed_params = None
+    if isinstance(params, dict):
+        processed_params = {}
+        for key, value in params.items():
+            if isinstance(value, list) or isinstance(value, tuple):
+                value_list = {"{}[{}]".format(key, i): i_value for i, i_value in enumerate(value)}
+                processed_params.update(value_list)
+            elif value is not None:
+                processed_params[key] = value
+    return processed_params
+
+
 def cleanup_params(params):
     return dict([(k, __safe_value(v)) for (k, v) in params.items() if v is not None and not v == ""])
 
@@ -499,18 +565,19 @@ def sign_request(params, options):
     api_secret = options.get("api_secret", cloudinary.config().api_secret)
     if not api_secret:
         raise ValueError("Must supply api_secret")
+    signature_algorithm = options.get("signature_algorithm", cloudinary.config().signature_algorithm)
 
     params = cleanup_params(params)
-    params["signature"] = api_sign_request(params, api_secret)
+    params["signature"] = api_sign_request(params, api_secret, signature_algorithm)
     params["api_key"] = api_key
 
     return params
 
 
-def api_sign_request(params_to_sign, api_secret):
+def api_sign_request(params_to_sign, api_secret, algorithm=SIGNATURE_SHA1):
     params = [(k + "=" + (",".join(v) if isinstance(v, list) else str(v))) for k, v in params_to_sign.items() if v]
     to_sign = "&".join(sorted(params))
-    return compute_hex_hash(to_sign + api_secret)
+    return compute_hex_hash(to_sign + api_secret, algorithm)
 
 
 def breakpoint_settings_mapper(breakpoint_settings):
@@ -667,6 +734,8 @@ def cloudinary_url(source, **options):
     url_suffix = options.pop("url_suffix", None)
     use_root_path = options.pop("use_root_path", cloudinary.config().use_root_path)
     auth_token = options.pop("auth_token", None)
+    long_url_signature = options.pop("long_url_signature", cloudinary.config().long_url_signature)
+    signature_algorithm = options.pop("signature_algorithm", cloudinary.config().signature_algorithm)
     if auth_token is not False:
         auth_token = merge(cloudinary.config().auth_token, auth_token)
 
@@ -692,9 +761,18 @@ def cloudinary_url(source, **options):
     signature = None
     if sign_url and not auth_token:
         to_sign = "/".join(__compact([transformation, source_to_sign]))
+        if long_url_signature:
+            # Long signature forces SHA256
+            signature_algorithm = SIGNATURE_SHA256
+            chars_length = LONG_URL_SIGNATURE_LENGTH
+        else:
+            chars_length = SHORT_URL_SIGNATURE_LENGTH
+        if signature_algorithm not in signature_algorithms:
+            raise ValueError("Unsupported signature algorithm '{}'".format(signature_algorithm))
+        hash_fn = signature_algorithms[signature_algorithm]
         signature = "s--" + to_string(
             base64.urlsafe_b64encode(
-                hashlib.sha1(to_bytes(to_sign + api_secret)).digest())[0:8]) + "--"
+                hash_fn(to_bytes(to_sign + api_secret)).digest())[0:chars_length]) + "--"
 
     prefix = unsigned_download_url_prefix(
         source, cloud_name, private_cdn, cdn_subdomain, secure_cdn_subdomain,
@@ -708,15 +786,30 @@ def cloudinary_url(source, **options):
     return source, options
 
 
-def cloudinary_api_url(action='upload', **options):
-    cloudinary_prefix = options.get("upload_prefix", cloudinary.config().upload_prefix)\
+def base_api_url(path, **options):
+    cloudinary_prefix = options.get("upload_prefix", cloudinary.config().upload_prefix) \
                         or "https://api.cloudinary.com"
     cloud_name = options.get("cloud_name", cloudinary.config().cloud_name)
+
     if not cloud_name:
         raise ValueError("Must supply cloud_name")
+
+    path = build_array(path)
+
+    return encode_unicode_url("/".join([cloudinary_prefix, cloudinary.API_VERSION, cloud_name] + path))
+
+
+def cloudinary_api_url(action='upload', **options):
     resource_type = options.get("resource_type", "image")
 
-    return encode_unicode_url("/".join([cloudinary_prefix, "v1_1", cloud_name, resource_type, action]))
+    return base_api_url([resource_type, action], **options)
+
+
+def cloudinary_api_download_url(action, params, **options):
+    params = params.copy()
+    params["mode"] = "download"
+    cloudinary_params = sign_request(params, options)
+    return cloudinary_api_url(action, **options) + "?" + urlencode(bracketize_seq(cloudinary_params), True)
 
 
 def cloudinary_scaled_url(source, width, transformation, options):
@@ -817,11 +910,7 @@ def bracketize_seq(params):
 
 
 def download_archive_url(**options):
-    params = options.copy()
-    params.update(mode="download")
-    cloudinary_params = sign_request(archive_params(**params), options)
-    return cloudinary_api_url("generate_archive", **options) + "?" + \
-        urlencode(bracketize_seq(cloudinary_params), True)
+    return cloudinary_api_download_url(action="generate_archive", params=archive_params(**options), **options)
 
 
 def download_zip_url(**options):
@@ -830,6 +919,47 @@ def download_zip_url(**options):
     return download_archive_url(**new_options)
 
 
+def download_folder(folder_path, **options):
+    """
+    Creates and returns a URL that when invoked creates an archive of a folder.
+    :param folder_path: The full path from the root that is used to generate download url.
+    :type folder_path:  str
+    :param options:     Additional options.
+    :type options:      dict, optional
+    :return:            Signed URL to download the folder.
+    :rtype:             str
+    """
+    options["prefixes"] = folder_path
+    options.setdefault("resource_type", "all")
+
+    return download_archive_url(**options)
+
+
+def download_backedup_asset(asset_id, version_id, **options):
+    """
+    The returned url allows downloading the backedup asset based on the the asset ID and the version ID.
+
+    Parameters asset_id and version_id are returned with api.resource(<PUBLIC_ID1>, versions=True) API call.
+
+    :param  asset_id:   The asset ID of the asset.
+    :type   asset_id:   str
+    :param  version_id: The version ID of the asset.
+    :type   version_id: str
+    :param  options:    Additional options.
+    :type   options:    dict, optional
+    :return:The signed URL for downloading backup version of the asset.
+    :rtype: str
+    """
+    params = {
+        "timestamp": options.get("timestamp", now()),
+        "asset_id": asset_id,
+        "version_id": version_id
+    }
+    cloudinary_params = sign_request(params, options)
+
+    return base_api_url("download_backup", **options) + "?" + urlencode(bracketize_seq(cloudinary_params), True)
+
+
 def generate_auth_token(**options):
     token_options = merge(cloudinary.config().auth_token, options)
     return auth_token.generate(**token_options)
@@ -919,8 +1049,8 @@ def build_upload_params(**options):
         "transformation": generate_transformation_string(**options)[0],
         "headers": build_custom_headers(options.get("headers")),
         "eager": build_eager(options.get("eager")),
-        "tags": options.get("tags") and ",".join(build_array(options["tags"])),
-        "allowed_formats": options.get("allowed_formats") and ",".join(build_array(options["allowed_formats"])),
+        "tags": options.get("tags") and encode_list(build_array(options["tags"])),
+        "allowed_formats": options.get("allowed_formats") and encode_list(build_array(options["allowed_formats"])),
         "face_coordinates": encode_double_array(options.get("face_coordinates")),
         "custom_coordinates": encode_double_array(options.get("custom_coordinates")),
         "context": encode_context(options.get("context")),
@@ -938,6 +1068,26 @@ def build_upload_params(**options):
     return params
 
 
+def build_multi_and_sprite_params(**options):
+    """
+    Build params for multi, download_multi, generate_sprite, and download_generated_sprite methods
+    """
+    tag = options.get("tag")
+    urls = options.get("urls")
+    if bool(tag) == bool(urls):
+        raise ValueError("Either 'tag' or 'urls' parameter has to be set but not both")
+    params = {
+        "mode": options.get("mode"),
+        "timestamp": now(),
+        "async": options.get("async"),
+        "notification_url": options.get("notification_url"),
+        "tag": tag,
+        "urls": urls,
+        "transformation": generate_transformation_string(fetch_format=options.get("format"), **options)[0]
+    }
+    return params
+
+
 def __process_text_options(layer, layer_parameter):
     font_family = layer.get("font_family")
     font_size = layer.get("font_size")
@@ -1067,22 +1217,38 @@ IF_OPERATORS = {
 
 PREDEFINED_VARS = {
     "aspect_ratio": "ar",
+    "aspectRatio": "ar",
     "current_page": "cp",
+    "currentPage": "cp",
     "face_count": "fc",
+    "faceCount": "fc",
     "height": "h",
     "initial_aspect_ratio": "iar",
+    "initialAspectRatio": "iar",
+    "trimmed_aspect_ratio": "tar",
+    "trimmedAspectRatio": "tar",
     "initial_height": "ih",
+    "initialHeight": "ih",
     "initial_width": "iw",
+    "initialWidth": "iw",
     "page_count": "pc",
+    "pageCount": "pc",
     "page_x": "px",
+    "pageX": "px",
     "page_y": "py",
+    "pageY": "py",
     "tags": "tags",
     "width": "w",
     "duration": "du",
     "initial_duration": "idu",
+    "initialDuration": "idu",
+    "illustration_score": "ils",
+    "illustrationScore": "ils",
+    "context": "ctx"
 }
 
-replaceRE = "((\\|\\||>=|<=|&&|!=|>|=|<|/|-|\\+|\\*|\^)(?=[ _])|(?<!\$)(" + '|'.join(PREDEFINED_VARS.keys()) + "))"
+replaceRE = "((\\|\\||>=|<=|&&|!=|>|=|<|/|-|\\+|\\*|\\^)(?=[ _])|(\\$_*[^_ ]+)|(?<!\\$)(" + \
+            '|'.join(PREDEFINED_VARS.keys()) + "))"
 
 
 def translate_if(match):
@@ -1277,13 +1443,15 @@ def check_property_enabled(f):
     return wrapper
 
 
-def verify_api_response_signature(public_id, version, signature):
+def verify_api_response_signature(public_id, version, signature, algorithm=None):
     """
     Verifies the authenticity of an API response signature
 
     :param public_id: The public id of the asset as returned in the API response
-    :param version: The version of the asset as returned in the API response
+    :param version:   The version of the asset as returned in the API response
     :param signature: Actual signature. Can be retrieved from the X-Cld-Signature header
+    :param algorithm: Name of hashing algorithm to use for calculation of HMACs.
+                      By default uses `cloudinary.config().signature_algorithm`
 
     :return: Boolean result of the validation
     """
@@ -1293,10 +1461,14 @@ def verify_api_response_signature(public_id, version, signature):
     parameters_to_sign = {'public_id': public_id,
                           'version': version}
 
-    return signature == api_sign_request(parameters_to_sign, cloudinary.config().api_secret)
+    return signature == api_sign_request(
+        parameters_to_sign,
+        cloudinary.config().api_secret,
+        algorithm or cloudinary.config().signature_algorithm
+    )
 
 
-def verify_notification_signature(body, timestamp, signature, valid_for=7200):
+def verify_notification_signature(body, timestamp, signature, valid_for=7200, algorithm=None):
     """
     Verifies the authenticity of a notification signature
 
@@ -1304,6 +1476,8 @@ def verify_notification_signature(body, timestamp, signature, valid_for=7200):
     :param timestamp: Unix timestamp. Can be retrieved from the X-Cld-Timestamp header
     :param signature: Actual signature. Can be retrieved from the X-Cld-Signature header
     :param valid_for: The desired time in seconds for considering the request valid
+    :param algorithm: Name of hashing algorithm to use for calculation of HMACs.
+                      By default uses `cloudinary.config().signature_algorithm`
 
     :return: Boolean result of the validation
     """
@@ -1316,7 +1490,9 @@ def verify_notification_signature(body, timestamp, signature, valid_for=7200):
     if not isinstance(body, str):
         raise ValueError('Body should be type of string')
 
-    return signature == compute_hex_hash('{}{}{}'.format(body, timestamp, cloudinary.config().api_secret))
+    return signature == compute_hex_hash(
+        '{}{}{}'.format(body, timestamp, cloudinary.config().api_secret),
+        algorithm or cloudinary.config().signature_algorithm)
 
 
 def get_http_connector(conf, options):
@@ -1332,3 +1508,26 @@ def get_http_connector(conf, options):
         return ProxyManager(conf.api_proxy, **options)
     else:
         return PoolManager(**options)
+
+
+def encode_list(obj):
+    if isinstance(obj, list):
+        return ",".join(obj)
+    return obj
+
+
+def safe_cast(val, casting_fn, default=None):
+    """
+    Attempts to cast a value to another using a given casting function
+    Will return a default value if casting fails (configurable, defaults to None)
+
+    :param val: The value to cast
+    :param casting_fn: The casting function that will receive the value to cast
+    :param default: The return value if casting fails
+
+    :return: Result of casting the value or the value of the default parameter
+    """
+    try:
+        return casting_fn(val)
+    except (ValueError, TypeError):
+        return default