Refs #23919 -- Removed misc references to Python 2.

18 files changed, 28 insertions, 88 deletions

diff --git a/django/apps/config.py b/django/apps/config.py
index 78762dd612..1bc684b3ca 100644
--- a/django/apps/config.py
+++ b/django/apps/config.py
@@ -17,7 +17,7 @@ class AppConfig:
         self.name = app_name
 
         # Root module for the application eg. <module 'django.contrib.admin'
-        # from 'django/contrib/admin/__init__.pyc'>.
+        # from 'django/contrib/admin/__init__.py'>.
         self.module = app_module
 
         # Reference to the Apps registry that holds this AppConfig. Set by the
@@ -37,13 +37,12 @@ class AppConfig:
             self.verbose_name = self.label.title()
 
         # Filesystem path to the application directory eg.
-        # u'/usr/lib/python2.7/dist-packages/django/contrib/admin'. Unicode on
-        # Python 2 and a str on Python 3.
+        # '/path/to/django/contrib/admin'.
         if not hasattr(self, 'path'):
             self.path = self._path_from_module(app_module)
 
         # Module containing models eg. <module 'django.contrib.admin.models'
-        # from 'django/contrib/admin/models.pyc'>. Set by import_models().
+        # from 'django/contrib/admin/models.py'>. Set by import_models().
         # None if the application doesn't have a models module.
         self.models_module = None
 
diff --git a/django/conf/project_template/manage.py-tpl b/django/conf/project_template/manage.py-tpl
index 41309844e0..9f83e65491 100755
--- a/django/conf/project_template/manage.py-tpl
+++ b/django/conf/project_template/manage.py-tpl
@@ -6,17 +6,10 @@ if __name__ == "__main__":
     os.environ.setdefault("DJANGO_SETTINGS_MODULE", "{{ project_name }}.settings")
     try:
         from django.core.management import execute_from_command_line
-    except ImportError:
-        # The above import may fail for some other reason. Ensure that the
-        # issue is really that Django is missing to avoid masking other
-        # exceptions on Python 2.
-        try:
-            import django
-        except ImportError:
-            raise ImportError(
-                "Couldn't import Django. Are you sure it's installed and "
-                "available on your PYTHONPATH environment variable? Did you "
-                "forget to activate a virtual environment?"
-            )
-        raise
+    except ImportError as exc:
+        raise ImportError(
+            "Couldn't import Django. Are you sure it's installed and "
+            "available on your PYTHONPATH environment variable? Did you "
+            "forget to activate a virtual environment?"
+        ) from exc
     execute_from_command_line(sys.argv)
diff --git a/django/contrib/gis/measure.py b/django/contrib/gis/measure.py
index fa3d7c34f2..d19737a118 100644
--- a/django/contrib/gis/measure.py
+++ b/django/contrib/gis/measure.py
@@ -159,9 +159,6 @@ class MeasureBase:
         else:
             raise TypeError('%(class)s must be divided with number or %(class)s' % {"class": pretty_name(self)})
 
-    def __div__(self, other):   # Python 2 compatibility
-        return type(self).__truediv__(self, other)
-
     def __itruediv__(self, other):
         if isinstance(other, NUMERIC_TYPES):
             self.standard /= float(other)
@@ -169,9 +166,6 @@ class MeasureBase:
         else:
             raise TypeError('%(class)s must be divided with number' % {"class": pretty_name(self)})
 
-    def __idiv__(self, other):  # Python 2 compatibility
-        return type(self).__itruediv__(self, other)
-
     def __bool__(self):
         return bool(self.standard)
 
@@ -333,9 +327,6 @@ class Area(MeasureBase):
         else:
             raise TypeError('%(class)s must be divided by a number' % {"class": pretty_name(self)})
 
-    def __div__(self, other):  # Python 2 compatibility
-        return type(self).__truediv__(self, other)
-
 
 # Shortcuts
 D = Distance
diff --git a/django/core/checks/model_checks.py b/django/core/checks/model_checks.py
index a8b5652662..2397fe3bb2 100644
--- a/django/core/checks/model_checks.py
+++ b/django/core/checks/model_checks.py
@@ -64,7 +64,7 @@ def _check_lazy_references(apps, ignore=None):
         operation, args, keywords = obj, [], {}
         while hasattr(operation, 'func'):
             # The or clauses are redundant but work around a bug (#25945) in
-            # functools.partial in Python 3 <= 3.5.1 and Python 2 <= 2.7.11.
+            # functools.partial in Python <= 3.5.1.
             args.extend(getattr(operation, 'args', []) or [])
             keywords.update(getattr(operation, 'keywords', {}) or {})
             operation = operation.func
diff --git a/django/core/files/temp.py b/django/core/files/temp.py
index f5aea1a9a8..d5c56a0ad0 100644
--- a/django/core/files/temp.py
+++ b/django/core/files/temp.py
@@ -9,8 +9,8 @@ if the same flag is not provided [1][2]. Note that this does not address the
 more general issue of opening a file for writing and reading in multiple
 processes in a manner that works across platforms.
 
-Also note that the custom version of NamedTemporaryFile does not support the
-full range of keyword arguments available in Python 2.6+ and 3.0+.
+The custom version of NamedTemporaryFile doesn't support the same keyword
+arguments available in tempfile.NamedTemporaryFile.
 
 1: https://mail.python.org/pipermail/python-list/2005-December/336957.html
 2: http://bugs.python.org/issue14243
@@ -30,10 +30,9 @@ if os.name == 'nt':
         Temporary file object constructor that supports reopening of the
         temporary file in Windows.
 
-        Note that unlike tempfile.NamedTemporaryFile from the standard library,
-        __init__() does not support the 'delete' keyword argument in
-        Python 2.6+, or the 'delete', 'buffering', 'encoding', or 'newline'
-        keyword arguments in Python 3.0+.
+        Unlike tempfile.NamedTemporaryFile from the standard library,
+        __init__() doesn't support the 'delete', 'buffering', 'encoding', or
+        'newline' keyword arguments.
         """
         def __init__(self, mode='w+b', bufsize=-1, suffix='', prefix='', dir=None):
             fd, name = tempfile.mkstemp(suffix=suffix, prefix=prefix, dir=dir)
diff --git a/django/core/servers/basehttp.py b/django/core/servers/basehttp.py
index a9ab0668f7..5a551b8ab1 100644
--- a/django/core/servers/basehttp.py
+++ b/django/core/servers/basehttp.py
@@ -83,7 +83,6 @@ class WSGIServer(simple_server.WSGIServer):
             super(WSGIServer, self).handle_error(request, client_address)
 
 
-# Inheriting from object required on Python 2.
 class ServerHandler(simple_server.ServerHandler):
     def handle_error(self):
         # Ignore broken pipe errors, otherwise pass on
diff --git a/django/db/backends/mysql/base.py b/django/db/backends/mysql/base.py
index d056392753..1b5dc864b0 100644
--- a/django/db/backends/mysql/base.py
+++ b/django/db/backends/mysql/base.py
@@ -2,7 +2,6 @@
 MySQL database backend for Django.
 
 Requires mysqlclient: https://pypi.python.org/pypi/mysqlclient/
-MySQLdb is supported for Python 2 only: http://sourceforge.net/projects/mysql-python
 """
 import re
 import sys
diff --git a/django/db/backends/oracle/introspection.py b/django/db/backends/oracle/introspection.py
index 7af2a18a8d..8a648dba3f 100644
--- a/django/db/backends/oracle/introspection.py
+++ b/django/db/backends/oracle/introspection.py
@@ -81,7 +81,7 @@ class DatabaseIntrospection(BaseDatabaseIntrospection):
             self.cache_bust_counter))
         description = []
         for desc in cursor.description:
-            name = force_text(desc[0])  # cx_Oracle always returns a 'str' on both Python 2 and 3
+            name = force_text(desc[0])  # cx_Oracle always returns a 'str'
             internal_size, default = field_map[name]
             name = name % {}  # cx_Oracle, for some reason, doubles percent signs.
             description.append(FieldInfo(*(name.lower(),) + desc[1:3] + (internal_size,) + desc[4:] + (default,)))
diff --git a/django/db/migrations/serializer.py b/django/db/migrations/serializer.py
index e15ffd87b5..58f90beaa2 100644
--- a/django/db/migrations/serializer.py
+++ b/django/db/migrations/serializer.py
@@ -160,24 +160,14 @@ class FunctionTypeSerializer(BaseSerializer):
             if "<" not in self.value.__qualname__:  # Qualname can include <locals>
                 return "%s.%s" % \
                     (self.value.__module__, self.value.__qualname__), {"import %s" % self.value.__module__}
-        # Python 2/fallback version
+        # Fallback version
         module_name = self.value.__module__
-        # Make sure it's actually there and not an unbound method
+        # Make sure it's actually there
         module = import_module(module_name)
         if not hasattr(module, self.value.__name__):
             raise ValueError(
-                "Could not find function %s in %s.\n"
-                "Please note that due to Python 2 limitations, you cannot "
-                "serialize unbound method functions (e.g. a method "
-                "declared and used in the same class body). Please move "
-                "the function into the main module body to use migrations.\n"
-                "For more information, see "
-                "https://docs.djangoproject.com/en/%s/topics/migrations/#serializing-values"
-                % (self.value.__name__, module_name, get_docs_version())
+                "Could not find function %s in %s.\n" % (self.value.__name__, module_name)
             )
-        # Needed on Python 2 only
-        if module_name == '__builtin__':
-            return self.value.__name__, set()
         return "%s.%s" % (module_name, self.value.__name__), {"import %s" % module_name}
 
 
diff --git a/django/db/models/expressions.py b/django/db/models/expressions.py
index de60a160e0..a1cec2393a 100644
--- a/django/db/models/expressions.py
+++ b/django/db/models/expressions.py
@@ -60,9 +60,6 @@ class Combinable:
     def __truediv__(self, other):
         return self._combine(other, self.DIV, False)
 
-    def __div__(self, other):  # Python 2 compatibility
-        return type(self).__truediv__(self, other)
-
     def __mod__(self, other):
         return self._combine(other, self.MOD, False)
 
@@ -103,9 +100,6 @@ class Combinable:
     def __rtruediv__(self, other):
         return self._combine(other, self.DIV, True)
 
-    def __rdiv__(self, other):  # Python 2 compatibility
-        return type(self).__rtruediv__(self, other)
-
     def __rmod__(self, other):
         return self._combine(other, self.MOD, True)
 
diff --git a/django/db/models/query_utils.py b/django/db/models/query_utils.py
index 54088b4fbb..c94a03f549 100644
--- a/django/db/models/query_utils.py
+++ b/django/db/models/query_utils.py
@@ -27,11 +27,8 @@ class InvalidQuery(Exception):
 
 def subclasses(cls):
     yield cls
-    # Python 2 lacks 'yield from', which could replace the inner loop
     for subclass in cls.__subclasses__():
-        # yield from subclasses(subclass)
-        for item in subclasses(subclass):
-            yield item
+        yield from subclasses(subclass)
 
 
 class QueryWrapper:
diff --git a/django/db/models/sql/compiler.py b/django/db/models/sql/compiler.py
index 1be406d704..5e5984dfb3 100644
--- a/django/db/models/sql/compiler.py
+++ b/django/db/models/sql/compiler.py
@@ -875,14 +875,8 @@ class SQLCompiler:
         try:
             cursor.execute(sql, params)
         except Exception:
-            try:
-                # Might fail for server-side cursors (e.g. connection closed)
-                cursor.close()
-            except Exception:
-                # Ignore clean up errors and raise the original error instead.
-                # Python 2 doesn't chain exceptions. Remove this error
-                # silencing when dropping Python 2 compatibility.
-                pass
+            # Might fail for server-side cursors (e.g. connection closed)
+            cursor.close()
             raise
 
         if result_type == CURSOR:
diff --git a/django/forms/utils.py b/django/forms/utils.py
index 59d70178f4..b23e6be0cc 100644
--- a/django/forms/utils.py
+++ b/django/forms/utils.py
@@ -1,5 +1,6 @@
 import json
 import sys
+from collections import UserList
 
 from django.conf import settings
 from django.core.exceptions import ValidationError  # backwards compatibility
@@ -8,11 +9,6 @@ from django.utils.encoding import force_text
 from django.utils.html import escape, format_html, format_html_join, html_safe
 from django.utils.translation import ugettext_lazy as _
 
-try:
-    from collections import UserList
-except ImportError:  # Python 2
-    from UserList import UserList
-
 
 def pretty_name(name):
     """Converts 'first_name' to 'First name'"""
diff --git a/django/test/utils.py b/django/test/utils.py
index 2bd6bb4d0f..ef837ce5c7 100644
--- a/django/test/utils.py
+++ b/django/test/utils.py
@@ -310,7 +310,7 @@ def get_runner(settings, test_runner_class=None):
         test_runner_class = settings.TEST_RUNNER
 
     test_path = test_runner_class.split('.')
-    # Allow for Python 2.5 relative paths
+    # Allow for relative paths
     if len(test_path) > 1:
         test_module_name = '.'.join(test_path[:-1])
     else:
diff --git a/django/utils/deconstruct.py b/django/utils/deconstruct.py
index 848b939b40..6bc70f7e53 100644
--- a/django/utils/deconstruct.py
+++ b/django/utils/deconstruct.py
@@ -24,7 +24,7 @@ def deconstructible(*args, **kwargs):
             Returns a 3-tuple of class import path, positional arguments,
             and keyword arguments.
             """
-            # Python 2/fallback version
+            # Fallback version
             if path:
                 module_name, _, name = path.rpartition('.')
             else:
diff --git a/django/utils/html.py b/django/utils/html.py
index fb9c18219c..f7f9a63350 100644
--- a/django/utils/html.py
+++ b/django/utils/html.py
@@ -172,9 +172,7 @@ def strip_tags(value):
     while '<' in value and '>' in value:
         new_value = _strip_once(value)
         if len(new_value) >= len(value):
-            # _strip_once was not able to detect more tags or length increased
-            # due to http://bugs.python.org/issue20288
-            # (affects Python 2 < 2.7.7 and Python 3 < 3.3.5)
+            # _strip_once was not able to detect more tags
             break
         value = new_value
     return value
diff --git a/django/utils/html_parser.py b/django/utils/html_parser.py
index e3e19ee9c3..6b46ddc368 100644
--- a/django/utils/html_parser.py
+++ b/django/utils/html_parser.py
@@ -11,9 +11,7 @@ except AttributeError:
 class HTMLParser(html.parser.HTMLParser):
     """Explicitly set convert_charrefs to be False.
 
-    This silences a deprecation warning on Python 3.4, but we can't do
-    it at call time because Python 2.7 does not have the keyword
-    argument.
+    This silences a deprecation warning on Python 3.4.
     """
     def __init__(self, convert_charrefs=False, **kwargs):
         html.parser.HTMLParser.__init__(self, convert_charrefs=convert_charrefs, **kwargs)
diff --git a/django/utils/translation/trans_real.py b/django/utils/translation/trans_real.py
index 62ff122621..c8913feb71 100644
--- a/django/utils/translation/trans_real.py
+++ b/django/utils/translation/trans_real.py
@@ -101,7 +101,6 @@ class DjangoTranslation(gettext_module.GNUTranslations):
         gettext_module.GNUTranslations.__init__(self)
         if domain is not None:
             self.domain = domain
-        self.set_output_charset('utf-8')  # For Python 2 gettext() (#25720)
 
         self.__language = language
         self.__to_language = to_language(language)
@@ -326,11 +325,7 @@ def do_translate(message, translation_function):
 
 
 def gettext(message):
-    """
-    Returns a string of the translation of the message.
-
-    Returns a string on Python 3 and an UTF-8-encoded bytestring on Python 2.
-    """
+    """Return a string of the translation of the message."""
     return do_translate(message, 'gettext')
 
 
@@ -372,8 +367,6 @@ def ngettext(singular, plural, number):
     """
     Returns a string of the translation of either the singular or plural,
     based on the number.
-
-    Returns a string on Python 3 and an UTF-8-encoded bytestring on Python 2.
     """
     return do_ntranslate(singular, plural, number, 'ngettext')