Add attribute sort helper function

plexpy/exporter.py

@@ -1643,8 +1643,7 @@ class Export(object):
 
             if self.file_format == 'csv':
                 csv_data = helpers.flatten_dict(result)
-                csv_headers = [field.split('.') for field in set().union(*csv_data)]
-                csv_headers = ['.'.join(field) for field in sorted(csv_headers, key=lambda s: (len(s), s))]
+                csv_headers = sorted(set().union(*csv_data), key=helpers.sort_attrs)
                 with open(filepath, 'w', encoding='utf-8', newline='') as outfile:
                     writer = csv.DictWriter(outfile, csv_headers)
                     writer.writeheader()

plexpy/helpers.py

@@ -1236,6 +1236,14 @@ def bool_true(value, return_none=False):
     return False
 
 
+def sort_attrs(attr):
+    if isinstance(attr, (list, tuple)):
+        a = attr[0].split('.')
+    else:
+        a = attr.split('.')
+    return len(a), a
+
+
 def get_attrs_to_dict(obj, attrs):
     d = {}