Update pytz to 2018.6

Update the pytz library files to those from the 2018.6 release.

lib/pytz/LICENSE.txt

@@ -1,4 +1,4 @@
-Copyright (c) 2003-2009 Stuart Bishop <stuart@stuartbishop.net>
+Copyright (c) 2003-2018 Stuart Bishop <stuart@stuartbishop.net>
 
 Permission is hereby granted, free of charge, to any person obtaining a
 copy of this software and associated documentation files (the "Software"),

lib/pytz/README.txt

@@ -87,13 +87,13 @@ localized time using the standard ``astimezone()`` method:
 Unfortunately using the tzinfo argument of the standard datetime
 constructors ''does not work'' with pytz for many timezones.
 
->>> datetime(2002, 10, 27, 12, 0, 0, tzinfo=amsterdam).strftime(fmt)
+>>> datetime(2002, 10, 27, 12, 0, 0, tzinfo=amsterdam).strftime(fmt)  # /!\ Does not work this way!
 '2002-10-27 12:00:00 LMT+0020'
 
 It is safe for timezones without daylight saving transitions though, such
 as UTC:
 
->>> datetime(2002, 10, 27, 12, 0, 0, tzinfo=pytz.utc).strftime(fmt)
+>>> datetime(2002, 10, 27, 12, 0, 0, tzinfo=pytz.utc).strftime(fmt)  # /!\ Not recommended except for UTC
 '2002-10-27 12:00:00 UTC+0000'
 
 The preferred way of dealing with times is to always work in UTC,
@@ -134,19 +134,21 @@ section for more details)
 >>> dt2.strftime(fmt)
 '2002-10-27 01:30:00 EST-0500'
 
-Converting between timezones also needs special attention. We also need
+Converting between timezones is more easily done, using the
-to use the ``normalize()`` method to ensure the conversion is correct.
+standard astimezone method.
 
 >>> utc_dt = utc.localize(datetime.utcfromtimestamp(1143408899))
 >>> utc_dt.strftime(fmt)
 '2006-03-26 21:34:59 UTC+0000'
 >>> au_tz = timezone('Australia/Sydney')
->>> au_dt = au_tz.normalize(utc_dt.astimezone(au_tz))
+>>> au_dt = utc_dt.astimezone(au_tz)
 >>> au_dt.strftime(fmt)
 '2006-03-27 08:34:59 AEDT+1100'
->>> utc_dt2 = utc.normalize(au_dt.astimezone(utc))
+>>> utc_dt2 = au_dt.astimezone(utc)
 >>> utc_dt2.strftime(fmt)
 '2006-03-26 21:34:59 UTC+0000'
+>>> utc_dt == utc_dt2
+True
 
 You can take shortcuts when dealing with the UTC side of timezone
 conversions. ``normalize()`` and ``localize()`` are not really
@@ -178,7 +180,7 @@ parameter to the ``utcoffset()``, ``dst()`` && ``tzname()`` methods.
 >>> ambiguous = datetime(2009, 10, 31, 23, 30)
 
 The ``is_dst`` parameter is ignored for most timestamps. It is only used
-during DST transition ambiguous periods to resulve that ambiguity.
+during DST transition ambiguous periods to resolve that ambiguity.
 
 >>> tz.utcoffset(normal, is_dst=True)
 datetime.timedelta(-1, 77400)
@@ -472,9 +474,9 @@ True
 True
 >>> 'Canada/Eastern' in common_timezones
 True
->>> 'US/Pacific-New' in all_timezones
+>>> 'Australia/Yancowinna' in all_timezones
 True
->>> 'US/Pacific-New' in common_timezones
+>>> 'Australia/Yancowinna' in common_timezones
 False
 
 Both ``common_timezones`` and ``all_timezones`` are alphabetically
@@ -510,6 +512,15 @@ Europe/Zurich
 Europe/Zurich
 
 
+Internationalization - i18n/l10n
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Pytz is an interface to the IANA database, which uses ASCII names. The `Unicode  Consortium's Unicode Locales (CLDR) <http://cldr.unicode.org>`_
+project provides translations. Thomas Khyn's
+`l18n <https://pypi.org/project/l18n/>`_ package can be used to access
+these translations from Python.
+
+
 License
 ~~~~~~~
 
@@ -527,12 +538,13 @@ Latest Versions
 
 This package will be updated after releases of the Olson timezone
 database.  The latest version can be downloaded from the `Python Package
-Index <http://pypi.python.org/pypi/pytz/>`_.  The code that is used
+Index <https://pypi.org/project/pytz/>`_.  The code that is used
 to generate this distribution is hosted on launchpad.net and available
-using the `Bazaar version control system <http://bazaar-vcs.org>`_
+using git::
-using::
 
-    bzr branch lp:pytz
+    git clone https://git.launchpad.net/pytz
+
+A mirror on github is also available at https://github.com/stub42/pytz
 
 Announcements of new releases are made on
 `Launchpad <https://launchpad.net/pytz>`_, and the
@@ -543,7 +555,7 @@ hosted there.
 Bugs, Feature Requests & Patches
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-Bugs can be reported using `Launchpad <https://bugs.launchpad.net/pytz>`_.
+Bugs can be reported using `Launchpad <https://bugs.launchpad.net/pytz>`__.
 
 
 Issues & Limitations

lib/pytz/__init__.py

@@ -8,12 +8,25 @@ See the datetime section of the Python Library Reference for information
 on how to use these modules.
 '''
 
+import sys
+import datetime
+import os.path
+
+from pytz.exceptions import AmbiguousTimeError
+from pytz.exceptions import InvalidTimeError
+from pytz.exceptions import NonExistentTimeError
+from pytz.exceptions import UnknownTimeZoneError
+from pytz.lazy import LazyDict, LazyList, LazySet
+from pytz.tzinfo import unpickler, BaseTzInfo
+from pytz.tzfile import build_tzinfo
+
+
 # The IANA (nee Olson) database is updated several times a year.
-OLSON_VERSION = '2016f'
+OLSON_VERSION = '2018f'
-VERSION = '2016.6.1'  # Switching to pip compatible version numbering.
+VERSION = '2018.6'  # pip compatible version number.
 __version__ = VERSION
 
-OLSEN_VERSION = OLSON_VERSION # Old releases had this misspelling
+OLSEN_VERSION = OLSON_VERSION  # Old releases had this misspelling
 
 __all__ = [
     'timezone', 'utc', 'country_timezones', 'country_names',
@@ -21,23 +34,11 @@ __all__ = [
     'NonExistentTimeError', 'UnknownTimeZoneError',
     'all_timezones', 'all_timezones_set',
     'common_timezones', 'common_timezones_set',
-    ]
+    'BaseTzInfo',
-
+]
-import sys, datetime, os.path, gettext
-
-from pytz.exceptions import AmbiguousTimeError
-from pytz.exceptions import InvalidTimeError
-from pytz.exceptions import NonExistentTimeError
-from pytz.exceptions import UnknownTimeZoneError
-from pytz.lazy import LazyDict, LazyList, LazySet
-from pytz.tzinfo import unpickler
-from pytz.tzfile import build_tzinfo, _byte_string
 
 
-try:
+if sys.version_info[0] > 2:  # Python 3.x
-    unicode
-
-except NameError: # Python 3.x
 
     # Python 3.x doesn't have unicode(), making writing code
     # for Python 2.3 and Python 3.x a pain.
@@ -52,10 +53,13 @@ except NameError: # Python 3.x
             ...
         UnicodeEncodeError: ...
         """
-        s.encode('ASCII') # Raise an exception if not ASCII
+        if type(s) == bytes:
-        return s # But return the original string - not a byte string.
+            s = s.decode('ASCII')
+        else:
+            s.encode('ASCII')  # Raise an exception if not ASCII
+        return s  # But the string - not a byte string.
 
-else: # Python 2.x
+else:  # Python 2.x
 
     def ascii(s):
         r"""
@@ -76,24 +80,31 @@ def open_resource(name):
 
     Uses the pkg_resources module if available and no standard file
     found at the calculated location.
+
+    It is possible to specify different location for zoneinfo
+    subdir by using the PYTZ_TZDATADIR environment variable.
     """
     name_parts = name.lstrip('/').split('/')
     for part in name_parts:
         if part == os.path.pardir or os.path.sep in part:
             raise ValueError('Bad path segment: %r' % part)
-    filename = os.path.join(os.path.dirname(__file__),
+    zoneinfo_dir = os.environ.get('PYTZ_TZDATADIR', None)
-                            'zoneinfo', *name_parts)
+    if zoneinfo_dir is not None:
-    if not os.path.exists(filename):
+        filename = os.path.join(zoneinfo_dir, *name_parts)
-        # http://bugs.launchpad.net/bugs/383171 - we avoid using this
+    else:
-        # unless absolutely necessary to help when a broken version of
+        filename = os.path.join(os.path.dirname(__file__),
-        # pkg_resources is installed.
+                                'zoneinfo', *name_parts)
-        try:
+        if not os.path.exists(filename):
-            from pkg_resources import resource_stream
+            # http://bugs.launchpad.net/bugs/383171 - we avoid using this
-        except ImportError:
+            # unless absolutely necessary to help when a broken version of
-            resource_stream = None
+            # pkg_resources is installed.
+            try:
+                from pkg_resources import resource_stream
+            except ImportError:
+                resource_stream = None
 
-        if resource_stream is not None:
+            if resource_stream is not None:
-            return resource_stream(__name__, 'zoneinfo/' + name)
+                return resource_stream(__name__, 'zoneinfo/' + name)
     return open(filename, 'rb')
 
 
@@ -106,23 +117,9 @@ def resource_exists(name):
         return False
 
 
-# Enable this when we get some translations?
-# We want an i18n API that is useful to programs using Python's gettext
-# module, as well as the Zope3 i18n package. Perhaps we should just provide
-# the POT file and translations, and leave it up to callers to make use
-# of them.
-#
-# t = gettext.translation(
-#         'pytz', os.path.join(os.path.dirname(__file__), 'locales'),
-#         fallback=True
-#         )
-# def _(timezone_name):
-#     """Translate a timezone name using the current locale, returning Unicode"""
-#     return t.ugettext(timezone_name)
-
-
 _tzinfo_cache = {}
 
+
 def timezone(zone):
     r''' Return a datetime.tzinfo implementation for the given timezone
 
@@ -192,7 +189,7 @@ ZERO = datetime.timedelta(0)
 HOUR = datetime.timedelta(hours=1)
 
 
-class UTC(datetime.tzinfo):
+class UTC(BaseTzInfo):
     """UTC
 
     Optimized UTC implementation. It unpickles using the single module global
@@ -288,7 +285,6 @@ def _p(*args):
 _p.__safe_for_unpickling__ = True
 
 
-
 class _CountryTimezoneDict(LazyDict):
     """Map ISO 3166 country code to a list of timezone names commonly used
     in that country.
@@ -374,7 +370,7 @@ country_names = _CountryNameDict()
 
 class _FixedOffset(datetime.tzinfo):
 
-    zone = None # to match the standard pytz API
+    zone = None  # to match the standard pytz API
 
     def __init__(self, minutes):
         if abs(minutes) >= 1440:
@@ -412,24 +408,24 @@ class _FixedOffset(datetime.tzinfo):
         return dt.astimezone(self)
 
 
-def FixedOffset(offset, _tzinfos = {}):
+def FixedOffset(offset, _tzinfos={}):
     """return a fixed-offset timezone based off a number of minutes.
 
         >>> one = FixedOffset(-330)
         >>> one
         pytz.FixedOffset(-330)
-        >>> one.utcoffset(datetime.datetime.now())
+        >>> str(one.utcoffset(datetime.datetime.now()))
-        datetime.timedelta(-1, 66600)
+        '-1 day, 18:30:00'
-        >>> one.dst(datetime.datetime.now())
+        >>> str(one.dst(datetime.datetime.now()))
-        datetime.timedelta(0)
+        '0:00:00'
 
         >>> two = FixedOffset(1380)
         >>> two
         pytz.FixedOffset(1380)
-        >>> two.utcoffset(datetime.datetime.now())
+        >>> str(two.utcoffset(datetime.datetime.now()))
-        datetime.timedelta(0, 82800)
+        '23:00:00'
-        >>> two.dst(datetime.datetime.now())
+        >>> str(two.dst(datetime.datetime.now()))
-        datetime.timedelta(0)
+        '0:00:00'
 
     The datetime.timedelta must be between the range of -1 and 1 day,
     non-inclusive.
@@ -482,14 +478,13 @@ FixedOffset.__safe_for_unpickling__ = True
 
 
 def _test():
-    import doctest, os, sys
+    import doctest
     sys.path.insert(0, os.pardir)
     import pytz
     return doctest.testmod(pytz)
 
 if __name__ == '__main__':
     _test()
-
 all_timezones = \
 ['Africa/Abidjan',
  'Africa/Accra',
@@ -676,6 +671,7 @@ all_timezones = \
  'America/Porto_Acre',
  'America/Porto_Velho',
  'America/Puerto_Rico',
+ 'America/Punta_Arenas',
  'America/Rainy_River',
  'America/Rankin_Inlet',
  'America/Recife',
@@ -731,6 +727,7 @@ all_timezones = \
  'Asia/Aqtobe',
  'Asia/Ashgabat',
  'Asia/Ashkhabad',
+ 'Asia/Atyrau',
  'Asia/Baghdad',
  'Asia/Bahrain',
  'Asia/Baku',
@@ -751,6 +748,7 @@ all_timezones = \
  'Asia/Dili',
  'Asia/Dubai',
  'Asia/Dushanbe',
+ 'Asia/Famagusta',
  'Asia/Gaza',
  'Asia/Harbin',
  'Asia/Hebron',
@@ -816,6 +814,7 @@ all_timezones = \
  'Asia/Vientiane',
  'Asia/Vladivostok',
  'Asia/Yakutsk',
+ 'Asia/Yangon',
  'Asia/Yekaterinburg',
  'Asia/Yerevan',
  'Atlantic/Azores',
@@ -861,7 +860,6 @@ all_timezones = \
  'CST6CDT',
  'Canada/Atlantic',
  'Canada/Central',
- 'Canada/East-Saskatchewan',
  'Canada/Eastern',
  'Canada/Mountain',
  'Canada/Newfoundland',
@@ -955,6 +953,7 @@ all_timezones = \
  'Europe/Samara',
  'Europe/San_Marino',
  'Europe/Sarajevo',
+ 'Europe/Saratov',
  'Europe/Simferopol',
  'Europe/Skopje',
  'Europe/Sofia',
@@ -1072,7 +1071,6 @@ all_timezones = \
  'US/Michigan',
  'US/Mountain',
  'US/Pacific',
- 'US/Pacific-New',
  'US/Samoa',
  'UTC',
  'Universal',
@@ -1252,6 +1250,7 @@ common_timezones = \
  'America/Port_of_Spain',
  'America/Porto_Velho',
  'America/Puerto_Rico',
+ 'America/Punta_Arenas',
  'America/Rainy_River',
  'America/Rankin_Inlet',
  'America/Recife',
@@ -1301,6 +1300,7 @@ common_timezones = \
  'Asia/Aqtau',
  'Asia/Aqtobe',
  'Asia/Ashgabat',
+ 'Asia/Atyrau',
  'Asia/Baghdad',
  'Asia/Bahrain',
  'Asia/Baku',
@@ -1317,6 +1317,7 @@ common_timezones = \
  'Asia/Dili',
  'Asia/Dubai',
  'Asia/Dushanbe',
+ 'Asia/Famagusta',
  'Asia/Gaza',
  'Asia/Hebron',
  'Asia/Ho_Chi_Minh',
@@ -1351,7 +1352,6 @@ common_timezones = \
  'Asia/Pyongyang',
  'Asia/Qatar',
  'Asia/Qyzylorda',
- 'Asia/Rangoon',
  'Asia/Riyadh',
  'Asia/Sakhalin',
  'Asia/Samarkand',
@@ -1372,6 +1372,7 @@ common_timezones = \
  'Asia/Vientiane',
  'Asia/Vladivostok',
  'Asia/Yakutsk',
+ 'Asia/Yangon',
  'Asia/Yekaterinburg',
  'Asia/Yerevan',
  'Atlantic/Azores',
@@ -1444,6 +1445,7 @@ common_timezones = \
  'Europe/Samara',
  'Europe/San_Marino',
  'Europe/Sarajevo',
+ 'Europe/Saratov',
  'Europe/Simferopol',
  'Europe/Skopje',
  'Europe/Sofia',
@@ -1489,7 +1491,6 @@ common_timezones = \
  'Pacific/Guadalcanal',
  'Pacific/Guam',
  'Pacific/Honolulu',
- 'Pacific/Johnston',
  'Pacific/Kiritimati',
  'Pacific/Kosrae',
  'Pacific/Kwajalein',

lib/pytz/exceptions.py

@@ -5,7 +5,7 @@ Custom exceptions raised by pytz.
 __all__ = [
     'UnknownTimeZoneError', 'InvalidTimeError', 'AmbiguousTimeError',
     'NonExistentTimeError',
-    ]
+]
 
 
 class UnknownTimeZoneError(KeyError):

lib/pytz/lazy.py

@@ -1,8 +1,11 @@
 from threading import RLock
 try:
-    from UserDict import DictMixin
+    from collections.abc import Mapping as DictMixin
-except ImportError:
+except ImportError:  # Python < 3.3
-    from collections import Mapping as DictMixin
+    try:
+        from UserDict import DictMixin  # Python 2
+    except ImportError:  # Python 3.0-3.3
+        from collections import Mapping as DictMixin
 
 
 # With lazy loading, we might end up with multiple threads triggering
@@ -13,6 +16,7 @@ _fill_lock = RLock()
 class LazyDict(DictMixin):
     """Dictionary populated on first use."""
     data = None
+
     def __getitem__(self, key):
         if self.data is None:
             _fill_lock.acquire()

lib/pytz/reference.py

@@ -5,17 +5,28 @@ Used for testing against as they are only correct for the years
 '''
 
 from datetime import tzinfo, timedelta, datetime
-from pytz import utc, UTC, HOUR, ZERO
+from pytz import HOUR, ZERO, UTC
+
+__all__ = [
+    'FixedOffset',
+    'LocalTimezone',
+    'USTimeZone',
+    'Eastern',
+    'Central',
+    'Mountain',
+    'Pacific',
+    'UTC'
+]
+
 
 # A class building tzinfo objects for fixed-offset time zones.
 # Note that FixedOffset(0, "UTC") is a different way to build a
 # UTC tzinfo object.
-
 class FixedOffset(tzinfo):
     """Fixed offset in minutes east from UTC."""
 
     def __init__(self, offset, name):
-        self.__offset = timedelta(minutes = offset)
+        self.__offset = timedelta(minutes=offset)
         self.__name = name
 
     def utcoffset(self, dt):
@@ -27,18 +38,19 @@ class FixedOffset(tzinfo):
     def dst(self, dt):
         return ZERO
 
-# A class capturing the platform's idea of local time.
 
 import time as _time
 
-STDOFFSET = timedelta(seconds = -_time.timezone)
+STDOFFSET = timedelta(seconds=-_time.timezone)
 if _time.daylight:
-    DSTOFFSET = timedelta(seconds = -_time.altzone)
+    DSTOFFSET = timedelta(seconds=-_time.altzone)
 else:
     DSTOFFSET = STDOFFSET
 
 DSTDIFF = DSTOFFSET - STDOFFSET
 
+
+# A class capturing the platform's idea of local time.
 class LocalTimezone(tzinfo):
 
     def utcoffset(self, dt):
@@ -66,7 +78,6 @@ class LocalTimezone(tzinfo):
 
 Local = LocalTimezone()
 
-# A complete implementation of current DST rules for major US time zones.
 
 def first_sunday_on_or_after(dt):
     days_to_go = 6 - dt.weekday()
@@ -74,12 +85,15 @@ def first_sunday_on_or_after(dt):
         dt += timedelta(days_to_go)
     return dt
 
+
 # In the US, DST starts at 2am (standard time) on the first Sunday in April.
 DSTSTART = datetime(1, 4, 1, 2)
 # and ends at 2am (DST time; 1am standard time) on the last Sunday of Oct.
 # which is the first Sunday on or after Oct 25.
 DSTEND = datetime(1, 10, 25, 1)
 
+
+# A complete implementation of current DST rules for major US time zones.
 class USTimeZone(tzinfo):
 
     def __init__(self, hours, reprname, stdname, dstname):
@@ -120,8 +134,7 @@ class USTimeZone(tzinfo):
         else:
             return ZERO
 
-Eastern  = USTimeZone(-5, "Eastern",  "EST", "EDT")
+Eastern = USTimeZone(-5, "Eastern", "EST", "EDT")
-Central  = USTimeZone(-6, "Central",  "CST", "CDT")
+Central = USTimeZone(-6, "Central", "CST", "CDT")
 Mountain = USTimeZone(-7, "Mountain", "MST", "MDT")
-Pacific  = USTimeZone(-8, "Pacific",  "PST", "PDT")
+Pacific = USTimeZone(-8, "Pacific", "PST", "PDT")
-

lib/pytz/tzfile.py

@@ -3,38 +3,37 @@
 $Id: tzfile.py,v 1.8 2004/06/03 00:15:24 zenzen Exp $
 '''
 
-try:
+from datetime import datetime
-    from cStringIO import StringIO
-except ImportError:
-    from io import StringIO
-from datetime import datetime, timedelta
 from struct import unpack, calcsize
 
 from pytz.tzinfo import StaticTzInfo, DstTzInfo, memorized_ttinfo
 from pytz.tzinfo import memorized_datetime, memorized_timedelta
 
+
 def _byte_string(s):
     """Cast a string or byte string to an ASCII byte string."""
     return s.encode('ASCII')
 
 _NULL = _byte_string('\0')
 
+
 def _std_string(s):
     """Cast a string or byte string to an ASCII string."""
     return str(s.decode('ASCII'))
 
+
 def build_tzinfo(zone, fp):
     head_fmt = '>4s c 15x 6l'
     head_size = calcsize(head_fmt)
-    (magic, format, ttisgmtcnt, ttisstdcnt,leapcnt, timecnt,
+    (magic, format, ttisgmtcnt, ttisstdcnt, leapcnt, timecnt,
-        typecnt, charcnt) =  unpack(head_fmt, fp.read(head_size))
+        typecnt, charcnt) = unpack(head_fmt, fp.read(head_size))
 
     # Make sure it is a tzfile(5) file
     assert magic == _byte_string('TZif'), 'Got magic %s' % repr(magic)
 
     # Read out the transition times, localtime indices and ttinfo structures.
     data_fmt = '>%(timecnt)dl %(timecnt)dB %(ttinfo)s %(charcnt)ds' % dict(
-        timecnt=timecnt, ttinfo='lBB'*typecnt, charcnt=charcnt)
+        timecnt=timecnt, ttinfo='lBB' * typecnt, charcnt=charcnt)
     data_size = calcsize(data_fmt)
     data = unpack(data_fmt, fp.read(data_size))
 
@@ -53,7 +52,7 @@ def build_tzinfo(zone, fp):
     i = 0
     while i < len(ttinfo_raw):
         # have we looked up this timezone name yet?
-        tzname_offset = ttinfo_raw[i+2]
+        tzname_offset = ttinfo_raw[i + 2]
         if tzname_offset not in tznames:
             nul = tznames_raw.find(_NULL, tzname_offset)
             if nul < 0:
@@ -61,12 +60,12 @@ def build_tzinfo(zone, fp):
             tznames[tzname_offset] = _std_string(
                 tznames_raw[tzname_offset:nul])
         ttinfo.append((ttinfo_raw[i],
-                       bool(ttinfo_raw[i+1]),
+                       bool(ttinfo_raw[i + 1]),
                        tznames[tzname_offset]))
         i += 3
 
     # Now build the timezone object
-    if len(ttinfo) ==1 or len(transitions) == 0:
+    if len(ttinfo) == 1 or len(transitions) == 0:
         ttinfo[0][0], ttinfo[0][2]
         cls = type(zone, (StaticTzInfo,), dict(
             zone=zone,
@@ -91,21 +90,21 @@ def build_tzinfo(zone, fp):
             if not inf[1]:
                 dst = 0
             else:
-                for j in range(i-1, -1, -1):
+                for j in range(i - 1, -1, -1):
                     prev_inf = ttinfo[lindexes[j]]
                     if not prev_inf[1]:
                         break
-                dst = inf[0] - prev_inf[0] # dst offset
+                dst = inf[0] - prev_inf[0]  # dst offset
 
                 # Bad dst? Look further. DST > 24 hours happens when
                 # a timzone has moved across the international dateline.
-                if dst <= 0 or dst > 3600*3:
+                if dst <= 0 or dst > 3600 * 3:
-                    for j in range(i+1, len(transitions)):
+                    for j in range(i + 1, len(transitions)):
                         stdinf = ttinfo[lindexes[j]]
                         if not stdinf[1]:
                             dst = inf[0] - stdinf[0]
                             if dst > 0:
-                                break # Found a useful std time.
+                                break  # Found a useful std time.
 
             tzname = inf[2]
 
@@ -129,9 +128,7 @@ if __name__ == '__main__':
     from pprint import pprint
     base = os.path.join(os.path.dirname(__file__), 'zoneinfo')
     tz = build_tzinfo('Australia/Melbourne',
-                      open(os.path.join(base,'Australia','Melbourne'), 'rb'))
+                      open(os.path.join(base, 'Australia', 'Melbourne'), 'rb'))
     tz = build_tzinfo('US/Eastern',
-                      open(os.path.join(base,'US','Eastern'), 'rb'))
+                      open(os.path.join(base, 'US', 'Eastern'), 'rb'))
     pprint(tz._utc_transition_times)
-    #print tz.asPython(4)
-    #print tz.transitions_mapping

lib/pytz/tzinfo.py

@@ -13,6 +13,8 @@ from pytz.exceptions import AmbiguousTimeError, NonExistentTimeError
 __all__ = []
 
 _timedelta_cache = {}
+
+
 def memorized_timedelta(seconds):
     '''Create only one instance of each distinct timedelta'''
     try:
@@ -24,6 +26,8 @@ def memorized_timedelta(seconds):
 
 _epoch = datetime.utcfromtimestamp(0)
 _datetime_cache = {0: _epoch}
+
+
 def memorized_datetime(seconds):
     '''Create only one instance of each distinct datetime'''
     try:
@@ -36,21 +40,24 @@ def memorized_datetime(seconds):
         return dt
 
 _ttinfo_cache = {}
+
+
 def memorized_ttinfo(*args):
     '''Create only one instance of each distinct tuple'''
     try:
         return _ttinfo_cache[args]
     except KeyError:
         ttinfo = (
-                memorized_timedelta(args[0]),
+            memorized_timedelta(args[0]),
-                memorized_timedelta(args[1]),
+            memorized_timedelta(args[1]),
-                args[2]
+            args[2]
-                )
+        )
         _ttinfo_cache[args] = ttinfo
         return ttinfo
 
 _notime = memorized_timedelta(0)
 
+
 def _to_seconds(td):
     '''Convert a timedelta to seconds'''
     return td.seconds + td.days * 24 * 60 * 60
@@ -154,14 +161,20 @@ class DstTzInfo(BaseTzInfo):
     timezone definition.
     '''
     # Overridden in subclass
-    _utc_transition_times = None # Sorted list of DST transition times in UTC
+
-    _transition_info = None # [(utcoffset, dstoffset, tzname)] corresponding
+    # Sorted list of DST transition times, UTC
-                            # to _utc_transition_times entries
+    _utc_transition_times = None
+
+    # [(utcoffset, dstoffset, tzname)] corresponding to
+    # _utc_transition_times entries
+    _transition_info = None
+
     zone = None
 
     # Set in __init__
+
     _tzinfos = None
-    _dst = None # DST offset
+    _dst = None  # DST offset
 
     def __init__(self, _inf=None, _tzinfos=None):
         if _inf:
@@ -170,7 +183,8 @@ class DstTzInfo(BaseTzInfo):
         else:
             _tzinfos = {}
             self._tzinfos = _tzinfos
-            self._utcoffset, self._dst, self._tzname = self._transition_info[0]
+            self._utcoffset, self._dst, self._tzname = (
+                self._transition_info[0])
             _tzinfos[self._transition_info[0]] = self
             for inf in self._transition_info[1:]:
                 if inf not in _tzinfos:
@@ -178,8 +192,8 @@ class DstTzInfo(BaseTzInfo):
 
     def fromutc(self, dt):
         '''See datetime.tzinfo.fromutc'''
-        if (dt.tzinfo is not None
+        if (dt.tzinfo is not None and
-            and getattr(dt.tzinfo, '_tzinfos', None) is not self._tzinfos):
+                getattr(dt.tzinfo, '_tzinfos', None) is not self._tzinfos):
             raise ValueError('fromutc: dt.tzinfo is not self')
         dt = dt.replace(tzinfo=None)
         idx = max(0, bisect_right(self._utc_transition_times, dt) - 1)
@@ -337,8 +351,8 @@ class DstTzInfo(BaseTzInfo):
             # obtain the correct timezone by winding the clock back.
             else:
                 return self.localize(
-                    dt - timedelta(hours=6), is_dst=False) + timedelta(hours=6)
+                    dt - timedelta(hours=6),
-
+                    is_dst=False) + timedelta(hours=6)
 
         # If we get this far, we have multiple possible timezones - this
         # is an ambiguous case occuring during the end-of-DST transition.
@@ -351,9 +365,8 @@ class DstTzInfo(BaseTzInfo):
         # Filter out the possiblilities that don't match the requested
         # is_dst
         filtered_possible_loc_dt = [
-            p for p in possible_loc_dt
+            p for p in possible_loc_dt if bool(p.tzinfo._dst) == is_dst
-                if bool(p.tzinfo._dst) == is_dst
+        ]
-            ]
 
         # Hopefully we only have one possibility left. Return it.
         if len(filtered_possible_loc_dt) == 1:
@@ -372,9 +385,10 @@ class DstTzInfo(BaseTzInfo):
         # Choose the earliest (by UTC) applicable timezone if is_dst=True
         # Choose the latest (by UTC) applicable timezone if is_dst=False
         # i.e., behave like end-of-DST transition
-        dates = {} # utc -> local
+        dates = {}  # utc -> local
         for local_dt in filtered_possible_loc_dt:
-            utc_time = local_dt.replace(tzinfo=None) - local_dt.tzinfo._utcoffset
+            utc_time = (
+                local_dt.replace(tzinfo=None) - local_dt.tzinfo._utcoffset)
             assert utc_time not in dates
             dates[utc_time] = local_dt
         return dates[[min, max][not is_dst](dates)]
@@ -389,11 +403,11 @@ class DstTzInfo(BaseTzInfo):
         >>> tz = timezone('America/St_Johns')
         >>> ambiguous = datetime(2009, 10, 31, 23, 30)
 
-        >>> tz.utcoffset(ambiguous, is_dst=False)
+        >>> str(tz.utcoffset(ambiguous, is_dst=False))
-        datetime.timedelta(-1, 73800)
+        '-1 day, 20:30:00'
 
-        >>> tz.utcoffset(ambiguous, is_dst=True)
+        >>> str(tz.utcoffset(ambiguous, is_dst=True))
-        datetime.timedelta(-1, 77400)
+        '-1 day, 21:30:00'
 
         >>> try:
         ...     tz.utcoffset(ambiguous)
@@ -421,19 +435,19 @@ class DstTzInfo(BaseTzInfo):
 
         >>> normal = datetime(2009, 9, 1)
 
-        >>> tz.dst(normal)
+        >>> str(tz.dst(normal))
-        datetime.timedelta(0, 3600)
+        '1:00:00'
-        >>> tz.dst(normal, is_dst=False)
+        >>> str(tz.dst(normal, is_dst=False))
-        datetime.timedelta(0, 3600)
+        '1:00:00'
-        >>> tz.dst(normal, is_dst=True)
+        >>> str(tz.dst(normal, is_dst=True))
-        datetime.timedelta(0, 3600)
+        '1:00:00'
 
         >>> ambiguous = datetime(2009, 10, 31, 23, 30)
 
-        >>> tz.dst(ambiguous, is_dst=False)
+        >>> str(tz.dst(ambiguous, is_dst=False))
-        datetime.timedelta(0)
+        '0:00:00'
-        >>> tz.dst(ambiguous, is_dst=True)
+        >>> str(tz.dst(ambiguous, is_dst=True))
-        datetime.timedelta(0, 3600)
+        '1:00:00'
         >>> try:
         ...     tz.dst(ambiguous)
         ... except AmbiguousTimeError:
@@ -494,23 +508,22 @@ class DstTzInfo(BaseTzInfo):
             dst = 'STD'
         if self._utcoffset > _notime:
             return '<DstTzInfo %r %s+%s %s>' % (
-                    self.zone, self._tzname, self._utcoffset, dst
+                self.zone, self._tzname, self._utcoffset, dst
-                )
+            )
         else:
             return '<DstTzInfo %r %s%s %s>' % (
-                    self.zone, self._tzname, self._utcoffset, dst
+                self.zone, self._tzname, self._utcoffset, dst
-                )
+            )
 
     def __reduce__(self):
         # Special pickle to zone remains a singleton and to cope with
         # database changes.
         return pytz._p, (
-                self.zone,
+            self.zone,
-                _to_seconds(self._utcoffset),
+            _to_seconds(self._utcoffset),
-                _to_seconds(self._dst),
+            _to_seconds(self._dst),
-                self._tzname
+            self._tzname
-                )
+        )
-
 
 
 def unpickler(zone, utcoffset=None, dstoffset=None, tzname=None):
@@ -549,8 +562,8 @@ def unpickler(zone, utcoffset=None, dstoffset=None, tzname=None):
     # get changed from the initial guess by the database maintainers to
     # match reality when this information is discovered.
     for localized_tz in tz._tzinfos.values():
-        if (localized_tz._utcoffset == utcoffset
+        if (localized_tz._utcoffset == utcoffset and
-                and localized_tz._dst == dstoffset):
+                localized_tz._dst == dstoffset):
             return localized_tz
 
     # This (utcoffset, dstoffset) information has been removed from the