Merge branch 'master' into schema-alteration

20 files changed, 158 insertions, 142 deletions

diff --git a/django/db/backends/__init__.py b/django/db/backends/__init__.py
index b9c642d093..5719f51445 100644
--- a/django/db/backends/__init__.py
+++ b/django/db/backends/__init__.py
@@ -621,16 +621,16 @@ class BaseDatabaseOperations(object):
         exists for database backends to provide a better implementation
         according to their own quoting schemes.
         """
-        from django.utils.encoding import smart_unicode, force_unicode
+        from django.utils.encoding import smart_text, force_text
 
         # Convert params to contain Unicode values.
-        to_unicode = lambda s: force_unicode(s, strings_only=True, errors='replace')
+        to_unicode = lambda s: force_text(s, strings_only=True, errors='replace')
         if isinstance(params, (list, tuple)):
             u_params = tuple([to_unicode(val) for val in params])
         else:
             u_params = dict([(to_unicode(k), to_unicode(v)) for k, v in params.items()])
 
-        return smart_unicode(sql) % u_params
+        return smart_text(sql) % u_params
 
     def last_insert_id(self, cursor, table_name, pk_name):
         """
@@ -814,8 +814,8 @@ class BaseDatabaseOperations(object):
 
     def prep_for_like_query(self, x):
         """Prepares a value for use in a LIKE query."""
-        from django.utils.encoding import smart_unicode
-        return smart_unicode(x).replace("\\", "\\\\").replace("%", "\%").replace("_", "\_")
+        from django.utils.encoding import smart_text
+        return smart_text(x).replace("\\", "\\\\").replace("%", "\%").replace("_", "\_")
 
     # Same as prep_for_like_query(), but called for "iexact" matches, which
     # need not necessarily be implemented using "LIKE" in the backend.
diff --git a/django/db/backends/creation.py b/django/db/backends/creation.py
index 4dffd78f44..0cc01cc876 100644
--- a/django/db/backends/creation.py
+++ b/django/db/backends/creation.py
@@ -3,6 +3,7 @@ import time
 
 from django.conf import settings
 from django.db.utils import load_backend
+from django.utils.six.moves import input
 
 # The prefix to put on the default database name when creating
 # the test database.
@@ -331,7 +332,7 @@ class BaseDatabaseCreation(object):
             sys.stderr.write(
                 "Got an error creating the test database: %s\n" % e)
             if not autoclobber:
-                confirm = raw_input(
+                confirm = input(
                     "Type 'yes' if you would like to try deleting the test "
                     "database '%s', or 'no' to cancel: " % test_database_name)
             if autoclobber or confirm == 'yes':
diff --git a/django/db/backends/mysql/introspection.py b/django/db/backends/mysql/introspection.py
index e6f18b819f..6aab0b99ab 100644
--- a/django/db/backends/mysql/introspection.py
+++ b/django/db/backends/mysql/introspection.py
@@ -1,4 +1,5 @@
 from django.db.backends import BaseDatabaseIntrospection
+from django.utils import six
 from MySQLdb import ProgrammingError, OperationalError
 from MySQLdb.constants import FIELD_TYPE
 import re
@@ -79,7 +80,7 @@ class DatabaseIntrospection(BaseDatabaseIntrospection):
         """
         Returns the name of the primary key column for the given table
         """
-        for column in self.get_indexes(cursor, table_name).iteritems():
+        for column in six.iteritems(self.get_indexes(cursor, table_name)):
             if column[1]['primary_key']:
                 return column[0]
         return None
diff --git a/django/db/backends/oracle/base.py b/django/db/backends/oracle/base.py
index b08113fed7..89cad12b6c 100644
--- a/django/db/backends/oracle/base.py
+++ b/django/db/backends/oracle/base.py
@@ -53,7 +53,7 @@ from django.db.backends.signals import connection_created
 from django.db.backends.oracle.client import DatabaseClient
 from django.db.backends.oracle.creation import DatabaseCreation
 from django.db.backends.oracle.introspection import DatabaseIntrospection
-from django.utils.encoding import smart_str, force_unicode
+from django.utils.encoding import smart_bytes, force_text
 from django.utils import six
 from django.utils import timezone
 
@@ -64,9 +64,9 @@ IntegrityError = Database.IntegrityError
 # Check whether cx_Oracle was compiled with the WITH_UNICODE option.  This will
 # also be True in Python 3.0.
 if int(Database.version.split('.', 1)[0]) >= 5 and not hasattr(Database, 'UNICODE'):
-    convert_unicode = force_unicode
+    convert_unicode = force_text
 else:
-    convert_unicode = smart_str
+    convert_unicode = smart_bytes
 
 
 class DatabaseFeatures(BaseDatabaseFeatures):
@@ -162,7 +162,7 @@ WHEN (new.%(col_name)s IS NULL)
         if isinstance(value, Database.LOB):
             value = value.read()
             if field and field.get_internal_type() == 'TextField':
-                value = force_unicode(value)
+                value = force_text(value)
 
         # Oracle stores empty strings as null. We need to undo this in
         # order to adhere to the Django convention of using the empty
@@ -245,7 +245,7 @@ WHEN (new.%(col_name)s IS NULL)
     def process_clob(self, value):
         if value is None:
             return ''
-        return force_unicode(value.read())
+        return force_text(value.read())
 
     def quote_name(self, name):
         # SQL92 requires delimited (quoted) names to be case-sensitive.  When
@@ -595,9 +595,9 @@ class OracleParam(object):
             param = param.astimezone(timezone.utc).replace(tzinfo=None)
 
         if hasattr(param, 'bind_parameter'):
-            self.smart_str = param.bind_parameter(cursor)
+            self.smart_bytes = param.bind_parameter(cursor)
         else:
-            self.smart_str = convert_unicode(param, cursor.charset,
+            self.smart_bytes = convert_unicode(param, cursor.charset,
                                              strings_only)
         if hasattr(param, 'input_size'):
             # If parameter has `input_size` attribute, use that.
@@ -676,7 +676,7 @@ class FormatStylePlaceholderCursor(object):
         self.setinputsizes(*sizes)
 
     def _param_generator(self, params):
-        return [p.smart_str for p in params]
+        return [p.smart_bytes for p in params]
 
     def execute(self, query, params=None):
         if params is None:
@@ -774,9 +774,11 @@ class CursorIterator(object):
     def __iter__(self):
         return self
 
-    def next(self):
+    def __next__(self):
         return _rowfactory(next(self.iter), self.cursor)
 
+    next = __next__             # Python 2 compatibility
+
 
 def _rowfactory(row, cursor):
     # Cast numeric values as the appropriate Python type based upon the
@@ -831,7 +833,7 @@ def to_unicode(s):
     unchanged).
     """
     if isinstance(s, six.string_types):
-        return force_unicode(s)
+        return force_text(s)
     return s
 
 
diff --git a/django/db/backends/oracle/creation.py b/django/db/backends/oracle/creation.py
index 2f096f735a..d9bf3dfea2 100644
--- a/django/db/backends/oracle/creation.py
+++ b/django/db/backends/oracle/creation.py
@@ -1,6 +1,7 @@
 import sys
 import time
 from django.db.backends.creation import BaseDatabaseCreation
+from django.utils.six.moves import input
 
 TEST_DATABASE_PREFIX = 'test_'
 PASSWORD = 'Im_a_lumberjack'
@@ -65,7 +66,7 @@ class DatabaseCreation(BaseDatabaseCreation):
             except Exception as e:
                 sys.stderr.write("Got an error creating the test database: %s\n" % e)
                 if not autoclobber:
-                    confirm = raw_input("It appears the test database, %s, already exists. Type 'yes' to delete it, or 'no' to cancel: " % TEST_NAME)
+                    confirm = input("It appears the test database, %s, already exists. Type 'yes' to delete it, or 'no' to cancel: " % TEST_NAME)
                 if autoclobber or confirm == 'yes':
                     try:
                         if verbosity >= 1:
@@ -87,7 +88,7 @@ class DatabaseCreation(BaseDatabaseCreation):
             except Exception as e:
                 sys.stderr.write("Got an error creating the test user: %s\n" % e)
                 if not autoclobber:
-                    confirm = raw_input("It appears the test user, %s, already exists. Type 'yes' to delete it, or 'no' to cancel: " % TEST_USER)
+                    confirm = input("It appears the test user, %s, already exists. Type 'yes' to delete it, or 'no' to cancel: " % TEST_USER)
                 if autoclobber or confirm == 'yes':
                     try:
                         if verbosity >= 1:
diff --git a/django/db/backends/sqlite3/base.py b/django/db/backends/sqlite3/base.py
index 0a97449789..0880079189 100644
--- a/django/db/backends/sqlite3/base.py
+++ b/django/db/backends/sqlite3/base.py
@@ -54,15 +54,15 @@ def adapt_datetime_with_timezone_support(value):
             default_timezone = timezone.get_default_timezone()
             value = timezone.make_aware(value, default_timezone)
         value = value.astimezone(timezone.utc).replace(tzinfo=None)
-    return value.isoformat(b" ")
+    return value.isoformat(str(" "))
 
-Database.register_converter(b"bool", lambda s: str(s) == '1')
-Database.register_converter(b"time", parse_time)
-Database.register_converter(b"date", parse_date)
-Database.register_converter(b"datetime", parse_datetime_with_timezone_support)
-Database.register_converter(b"timestamp", parse_datetime_with_timezone_support)
-Database.register_converter(b"TIMESTAMP", parse_datetime_with_timezone_support)
-Database.register_converter(b"decimal", util.typecast_decimal)
+Database.register_converter(str("bool"), lambda s: str(s) == '1')
+Database.register_converter(str("time"), parse_time)
+Database.register_converter(str("date"), parse_date)
+Database.register_converter(str("datetime"), parse_datetime_with_timezone_support)
+Database.register_converter(str("timestamp"), parse_datetime_with_timezone_support)
+Database.register_converter(str("TIMESTAMP"), parse_datetime_with_timezone_support)
+Database.register_converter(str("decimal"), util.typecast_decimal)
 Database.register_adapter(datetime.datetime, adapt_datetime_with_timezone_support)
 Database.register_adapter(decimal.Decimal, util.rev_typecast_decimal)
 if Database.version_info >= (2, 4, 1):
diff --git a/django/db/backends/sqlite3/creation.py b/django/db/backends/sqlite3/creation.py
index efdc457be0..c022b56c85 100644
--- a/django/db/backends/sqlite3/creation.py
+++ b/django/db/backends/sqlite3/creation.py
@@ -1,6 +1,7 @@
 import os
 import sys
 from django.db.backends.creation import BaseDatabaseCreation
+from django.utils.six.moves import input
 
 class DatabaseCreation(BaseDatabaseCreation):
     # SQLite doesn't actually support most of these types, but it "does the right
@@ -53,7 +54,7 @@ class DatabaseCreation(BaseDatabaseCreation):
                 print("Destroying old test database '%s'..." % self.connection.alias)
             if os.access(test_database_name, os.F_OK):
                 if not autoclobber:
-                    confirm = raw_input("Type 'yes' if you would like to try deleting the test database '%s', or 'no' to cancel: " % test_database_name)
+                    confirm = input("Type 'yes' if you would like to try deleting the test database '%s', or 'no' to cancel: " % test_database_name)
                 if autoclobber or confirm == 'yes':
                   try:
                       os.remove(test_database_name)
diff --git a/django/db/models/base.py b/django/db/models/base.py
index 002e2aff65..569b8e876c 100644
--- a/django/db/models/base.py
+++ b/django/db/models/base.py
@@ -23,11 +23,35 @@ from django.db.models import signals
 from django.db.models.loading import register_models, get_model
 from django.utils.translation import ugettext_lazy as _
 from django.utils.functional import curry
-from django.utils.encoding import smart_str, force_unicode
+from django.utils.encoding import smart_bytes, force_text
 from django.utils import six
 from django.utils.text import get_text_list, capfirst
 
 
+def subclass_exception(name, parents, module, attached_to=None):
+    """
+    Create exception subclass. Used by ModelBase below.
+
+    If 'attached_to' is supplied, the exception will be created in a way that
+    allows it to be pickled, assuming the returned exception class will be added
+    as an attribute to the 'attached_to' class.
+    """
+    class_dict = {'__module__': module}
+    if attached_to is not None:
+        def __reduce__(self):
+            # Exceptions are special - they've got state that isn't
+            # in self.__dict__. We assume it is all in self.args.
+            return (unpickle_inner_exception, (attached_to, name), self.args)
+
+        def __setstate__(self, args):
+            self.args = args
+
+        class_dict['__reduce__'] = __reduce__
+        class_dict['__setstate__'] = __setstate__
+
+    return type(name, parents, class_dict)
+
+
 class ModelBase(type):
     """
     Metaclass for all models.
@@ -63,12 +87,12 @@ class ModelBase(type):
 
         new_class.add_to_class('_meta', Options(meta, **kwargs))
         if not abstract:
-            new_class.add_to_class('DoesNotExist', subclass_exception(b'DoesNotExist',
+            new_class.add_to_class('DoesNotExist', subclass_exception(str('DoesNotExist'),
                     tuple(x.DoesNotExist
                           for x in parents if hasattr(x, '_meta') and not x._meta.abstract)
                     or (ObjectDoesNotExist,),
                     module, attached_to=new_class))
-            new_class.add_to_class('MultipleObjectsReturned', subclass_exception(b'MultipleObjectsReturned',
+            new_class.add_to_class('MultipleObjectsReturned', subclass_exception(str('MultipleObjectsReturned'),
                     tuple(x.MultipleObjectsReturned
                           for x in parents if hasattr(x, '_meta') and not x._meta.abstract)
                     or (MultipleObjectsReturned,),
@@ -364,14 +388,14 @@ class Model(six.with_metaclass(ModelBase, object)):
                 setattr(self, field.attname, val)
 
         if kwargs:
-            for prop in kwargs.keys():
+            for prop in list(kwargs):
                 try:
                     if isinstance(getattr(self.__class__, prop), property):
                         setattr(self, prop, kwargs.pop(prop))
                 except AttributeError:
                     pass
             if kwargs:
-                raise TypeError("'%s' is an invalid keyword argument for this function" % kwargs.keys()[0])
+                raise TypeError("'%s' is an invalid keyword argument for this function" % list(kwargs)[0])
         super(Model, self).__init__()
         signals.post_init.send(sender=self.__class__, instance=self)
 
@@ -380,11 +404,11 @@ class Model(six.with_metaclass(ModelBase, object)):
             u = six.text_type(self)
         except (UnicodeEncodeError, UnicodeDecodeError):
             u = '[Bad Unicode data]'
-        return smart_str('<%s: %s>' % (self.__class__.__name__, u))
+        return smart_bytes('<%s: %s>' % (self.__class__.__name__, u))
 
     def __str__(self):
         if hasattr(self, '__unicode__'):
-            return force_unicode(self).encode('utf-8')
+            return force_text(self).encode('utf-8')
         return '%s object' % self.__class__.__name__
 
     def __eq__(self, other):
@@ -605,14 +629,14 @@ class Model(six.with_metaclass(ModelBase, object)):
 
     def _get_FIELD_display(self, field):
         value = getattr(self, field.attname)
-        return force_unicode(dict(field.flatchoices).get(value, value), strings_only=True)
+        return force_text(dict(field.flatchoices).get(value, value), strings_only=True)
 
     def _get_next_or_previous_by_FIELD(self, field, is_next, **kwargs):
         if not self.pk:
             raise ValueError("get_next/get_previous cannot be used on unsaved objects.")
         op = is_next and 'gt' or 'lt'
         order = not is_next and '-' or ''
-        param = smart_str(getattr(self, field.attname))
+        param = smart_bytes(getattr(self, field.attname))
         q = Q(**{'%s__%s' % (field.name, op): param})
         q = q|Q(**{field.name: param, 'pk__%s' % op: self.pk})
         qs = self.__class__._default_manager.using(self._state.db).filter(**kwargs).filter(q).order_by('%s%s' % (order, field.name), '%spk' % order)
@@ -929,29 +953,6 @@ def model_unpickle(model, attrs):
     return cls.__new__(cls)
 model_unpickle.__safe_for_unpickle__ = True
 
-def subclass_exception(name, parents, module, attached_to=None):
-    """
-    Create exception subclass.
-
-    If 'attached_to' is supplied, the exception will be created in a way that
-    allows it to be pickled, assuming the returned exception class will be added
-    as an attribute to the 'attached_to' class.
-    """
-    class_dict = {'__module__': module}
-    if attached_to is not None:
-        def __reduce__(self):
-            # Exceptions are special - they've got state that isn't
-            # in self.__dict__. We assume it is all in self.args.
-            return (unpickle_inner_exception, (attached_to, name), self.args)
-
-        def __setstate__(self, args):
-            self.args = args
-
-        class_dict['__reduce__'] = __reduce__
-        class_dict['__setstate__'] = __setstate__
-
-    return type(name, parents, class_dict)
-
 def unpickle_inner_exception(klass, exception_name):
     # Get the exception class from the class it is attached to:
     exception = getattr(klass, exception_name)
diff --git a/django/db/models/deletion.py b/django/db/models/deletion.py
index d8bb8f2e66..4449b75a81 100644
--- a/django/db/models/deletion.py
+++ b/django/db/models/deletion.py
@@ -4,6 +4,7 @@ from operator import attrgetter
 from django.db import connections, transaction, IntegrityError
 from django.db.models import signals, sql
 from django.utils.datastructures import SortedDict
+from django.utils import six
 
 
 class ProtectedError(IntegrityError):
@@ -157,7 +158,7 @@ class Collector(object):
         # Recursively collect concrete model's parent models, but not their
         # related objects. These will be found by meta.get_all_related_objects()
         concrete_model = model._meta.concrete_model
-        for ptr in concrete_model._meta.parents.itervalues():
+        for ptr in six.itervalues(concrete_model._meta.parents):
             if ptr:
                 parent_objs = [getattr(obj, ptr.name) for obj in new_objs]
                 self.collect(parent_objs, source=model,
@@ -199,14 +200,14 @@ class Collector(object):
         )
 
     def instances_with_model(self):
-        for model, instances in self.data.iteritems():
+        for model, instances in six.iteritems(self.data):
             for obj in instances:
                 yield model, obj
 
     def sort(self):
         sorted_models = []
         concrete_models = set()
-        models = self.data.keys()
+        models = list(self.data)
         while len(sorted_models) < len(models):
             found = False
             for model in models:
@@ -241,24 +242,24 @@ class Collector(object):
                 )
 
         # update fields
-        for model, instances_for_fieldvalues in self.field_updates.iteritems():
+        for model, instances_for_fieldvalues in six.iteritems(self.field_updates):
             query = sql.UpdateQuery(model)
-            for (field, value), instances in instances_for_fieldvalues.iteritems():
+            for (field, value), instances in six.iteritems(instances_for_fieldvalues):
                 query.update_batch([obj.pk for obj in instances],
                                    {field.name: value}, self.using)
 
         # reverse instance collections
-        for instances in self.data.itervalues():
+        for instances in six.itervalues(self.data):
             instances.reverse()
 
         # delete batches
-        for model, batches in self.batches.iteritems():
+        for model, batches in six.iteritems(self.batches):
             query = sql.DeleteQuery(model)
-            for field, instances in batches.iteritems():
+            for field, instances in six.iteritems(batches):
                 query.delete_batch([obj.pk for obj in instances], self.using, field)
 
         # delete instances
-        for model, instances in self.data.iteritems():
+        for model, instances in six.iteritems(self.data):
             query = sql.DeleteQuery(model)
             pk_list = [obj.pk for obj in instances]
             query.delete_batch(pk_list, self.using)
@@ -271,10 +272,10 @@ class Collector(object):
                 )
 
         # update collected instances
-        for model, instances_for_fieldvalues in self.field_updates.iteritems():
-            for (field, value), instances in instances_for_fieldvalues.iteritems():
+        for model, instances_for_fieldvalues in six.iteritems(self.field_updates):
+            for (field, value), instances in six.iteritems(instances_for_fieldvalues):
                 for obj in instances:
                     setattr(obj, field.attname, value)
-        for model, instances in self.data.iteritems():
+        for model, instances in six.iteritems(self.data):
             for instance in instances:
                 setattr(instance, model._meta.pk.attname, None)
diff --git a/django/db/models/fields/__init__.py b/django/db/models/fields/__init__.py
index 9606b1b843..d07851bbf5 100644
--- a/django/db/models/fields/__init__.py
+++ b/django/db/models/fields/__init__.py
@@ -19,7 +19,7 @@ from django.utils.functional import curry, total_ordering
 from django.utils.text import capfirst
 from django.utils import timezone
 from django.utils.translation import ugettext_lazy as _
-from django.utils.encoding import smart_unicode, force_unicode
+from django.utils.encoding import smart_text, force_text
 from django.utils.ipv6 import clean_ipv6_address
 from django.utils import six
 
@@ -135,6 +135,8 @@ class Field(object):
             return self.creation_counter < other.creation_counter
         return NotImplemented
 
+    __hash__ = object.__hash__
+
     def __deepcopy__(self, memodict):
         # We don't have to deepcopy very much here, since most things are not
         # intended to be altered after initial creation.
@@ -179,7 +181,8 @@ class Field(object):
         if not self.editable:
             # Skip validation for non-editable fields.
             return
-        if self._choices and value:
+
+        if self._choices and value not in validators.EMPTY_VALUES:
             for option_key, option_value in self.choices:
                 if isinstance(option_value, (list, tuple)):
                     # This is an optgroup, so look inside the group for
@@ -385,7 +388,7 @@ class Field(object):
         if self.has_default():
             if callable(self.default):
                 return self.default()
-            return force_unicode(self.default, strings_only=True)
+            return force_text(self.default, strings_only=True)
         if (not self.empty_strings_allowed or (self.null and
                    not connection.features.interprets_empty_strings_as_nulls)):
             return None
@@ -403,11 +406,11 @@ class Field(object):
         rel_model = self.rel.to
         if hasattr(self.rel, 'get_related_field'):
             lst = [(getattr(x, self.rel.get_related_field().attname),
-                        smart_unicode(x))
+                        smart_text(x))
                    for x in rel_model._default_manager.complex_filter(
                        self.rel.limit_choices_to)]
         else:
-            lst = [(x._get_pk_val(), smart_unicode(x))
+            lst = [(x._get_pk_val(), smart_text(x))
                    for x in rel_model._default_manager.complex_filter(
                        self.rel.limit_choices_to)]
         return first_choice + lst
@@ -434,7 +437,7 @@ class Field(object):
         Returns a string value of this field from the passed obj.
         This is used by the serialization framework.
         """
-        return smart_unicode(self._get_val_from_obj(obj))
+        return smart_text(self._get_val_from_obj(obj))
 
     def bind(self, fieldmapping, original, bound_field_class):
         return bound_field_class(self, fieldmapping, original)
@@ -486,7 +489,7 @@ class Field(object):
             # Many of the subclass-specific formfield arguments (min_value,
             # max_value) don't apply for choice fields, so be sure to only pass
             # the values that TypedChoiceField will understand.
-            for k in kwargs.keys():
+            for k in list(kwargs):
                 if k not in ('coerce', 'empty_value', 'choices', 'required',
                              'widget', 'label', 'initial', 'help_text',
                              'error_messages', 'show_hidden_initial'):
@@ -628,7 +631,7 @@ class CharField(Field):
     def to_python(self, value):
         if isinstance(value, six.string_types) or value is None:
             return value
-        return smart_unicode(value)
+        return smart_text(value)
 
     def get_prep_value(self, value):
         return self.to_python(value)
@@ -1188,7 +1191,7 @@ class TextField(Field):
     def get_prep_value(self, value):
         if isinstance(value, six.string_types) or value is None:
             return value
-        return smart_unicode(value)
+        return smart_text(value)
 
     def formfield(self, **kwargs):
         defaults = {'widget': forms.Textarea}
diff --git a/django/db/models/fields/files.py b/django/db/models/fields/files.py
index b51ef1d5d6..ad4c36ca0d 100644
--- a/django/db/models/fields/files.py
+++ b/django/db/models/fields/files.py
@@ -8,7 +8,7 @@ from django.core.files.base import File
 from django.core.files.storage import default_storage
 from django.core.files.images import ImageFile
 from django.db.models import signals
-from django.utils.encoding import force_unicode, smart_str
+from django.utils.encoding import force_text, smart_bytes
 from django.utils import six
 from django.utils.translation import ugettext_lazy as _
 
@@ -280,7 +280,7 @@ class FileField(Field):
         setattr(cls, self.name, self.descriptor_class(self))
 
     def get_directory_name(self):
-        return os.path.normpath(force_unicode(datetime.datetime.now().strftime(smart_str(self.upload_to))))
+        return os.path.normpath(force_text(datetime.datetime.now().strftime(smart_bytes(self.upload_to))))
 
     def get_filename(self, filename):
         return os.path.normpath(self.storage.get_valid_name(os.path.basename(filename)))
diff --git a/django/db/models/fields/related.py b/django/db/models/fields/related.py
index 2a2502b54f..08cc0a747f 100644
--- a/django/db/models/fields/related.py
+++ b/django/db/models/fields/related.py
@@ -9,7 +9,7 @@ from django.db.models.related import RelatedObject
 from django.db.models.query import QuerySet
 from django.db.models.query_utils import QueryWrapper
 from django.db.models.deletion import CASCADE
-from django.utils.encoding import smart_unicode
+from django.utils.encoding import smart_text
 from django.utils import six
 from django.utils.translation import ugettext_lazy as _, string_concat
 from django.utils.functional import curry, cached_property
@@ -241,7 +241,7 @@ class SingleRelatedObjectDescriptor(object):
         rel_obj_attr = attrgetter(self.related.field.attname)
         instance_attr = lambda obj: obj._get_pk_val()
         instances_dict = dict((instance_attr(inst), inst) for inst in instances)
-        params = {'%s__pk__in' % self.related.field.name: instances_dict.keys()}
+        params = {'%s__pk__in' % self.related.field.name: list(instances_dict)}
         qs = self.get_query_set(instance=instances[0]).filter(**params)
         # Since we're going to assign directly in the cache,
         # we must manage the reverse relation cache manually.
@@ -335,9 +335,9 @@ class ReverseSingleRelatedObjectDescriptor(object):
         instance_attr = attrgetter(self.field.attname)
         instances_dict = dict((instance_attr(inst), inst) for inst in instances)
         if other_field.rel:
-            params = {'%s__pk__in' % self.field.rel.field_name: instances_dict.keys()}
+            params = {'%s__pk__in' % self.field.rel.field_name: list(instances_dict)}
         else:
-            params = {'%s__in' % self.field.rel.field_name: instances_dict.keys()}
+            params = {'%s__in' % self.field.rel.field_name: list(instances_dict)}
         qs = self.get_query_set(instance=instances[0]).filter(**params)
         # Since we're going to assign directly in the cache,
         # we must manage the reverse relation cache manually.
@@ -488,7 +488,7 @@ class ForeignRelatedObjectsDescriptor(object):
                 instance_attr = attrgetter(attname)
                 instances_dict = dict((instance_attr(inst), inst) for inst in instances)
                 db = self._db or router.db_for_read(self.model, instance=instances[0])
-                query = {'%s__%s__in' % (rel_field.name, attname): instances_dict.keys()}
+                query = {'%s__%s__in' % (rel_field.name, attname): list(instances_dict)}
                 qs = super(RelatedManager, self).get_query_set().using(db).filter(**query)
                 # Since we just bypassed this class' get_query_set(), we must manage
                 # the reverse relation manually.
@@ -999,7 +999,7 @@ class ForeignKey(RelatedField, Field):
             if not self.blank and self.choices:
                 choice_list = self.get_choices_default()
                 if len(choice_list) == 2:
-                    return smart_unicode(choice_list[1][0])
+                    return smart_text(choice_list[1][0])
         return Field.value_to_string(self, obj)
 
     def contribute_to_class(self, cls, name):
@@ -1205,7 +1205,7 @@ class ManyToManyField(RelatedField, Field):
                 choices_list = self.get_choices_default()
                 if len(choices_list) == 1:
                     data = [choices_list[0][0]]
-        return smart_unicode(data)
+        return smart_text(data)
 
     def contribute_to_class(self, cls, name):
         # To support multiple relations to self, it's useful to have a non-None
diff --git a/django/db/models/loading.py b/django/db/models/loading.py
index d651584e7a..7a9cb2cb41 100644
--- a/django/db/models/loading.py
+++ b/django/db/models/loading.py
@@ -5,6 +5,7 @@ from django.core.exceptions import ImproperlyConfigured
 from django.utils.datastructures import SortedDict
 from django.utils.importlib import import_module
 from django.utils.module_loading import module_has_submodule
+from django.utils import six
 
 import imp
 import sys
@@ -193,9 +194,9 @@ class AppCache(object):
         else:
             if only_installed:
                 app_list = [self.app_models.get(app_label, SortedDict())
-                            for app_label in self.app_labels.iterkeys()]
+                            for app_label in six.iterkeys(self.app_labels)]
             else:
-                app_list = self.app_models.itervalues()
+                app_list = six.itervalues(self.app_models)
         model_list = []
         for app in app_list:
             model_list.extend(
diff --git a/django/db/models/options.py b/django/db/models/options.py
index 7308a15c6b..2e8ccb49ce 100644
--- a/django/db/models/options.py
+++ b/django/db/models/options.py
@@ -8,7 +8,7 @@ from django.db.models.fields import AutoField, FieldDoesNotExist
 from django.db.models.fields.proxy import OrderWrt
 from django.db.models.loading import get_models, app_cache_ready
 from django.utils.translation import activate, deactivate_all, get_language, string_concat
-from django.utils.encoding import force_unicode, smart_str
+from django.utils.encoding import force_text, smart_bytes
 from django.utils.datastructures import SortedDict
 from django.utils import six
 
@@ -127,7 +127,7 @@ class Options(object):
             if self.parents:
                 # Promote the first parent link in lieu of adding yet another
                 # field.
-                field = next(self.parents.itervalues())
+                field = next(six.itervalues(self.parents))
                 # Look for a local field with the same name as the
                 # first parent link. If a local field has already been
                 # created, use it instead of promoting the parent
@@ -147,13 +147,13 @@ class Options(object):
         # self.duplicate_targets will map each duplicate field column to the
         # columns it duplicates.
         collections = {}
-        for column, target in self.duplicate_targets.iteritems():
+        for column, target in six.iteritems(self.duplicate_targets):
             try:
                 collections[target].add(column)
             except KeyError:
                 collections[target] = set([column])
         self.duplicate_targets = {}
-        for elt in collections.itervalues():
+        for elt in six.itervalues(collections):
             if len(elt) == 1:
                 continue
             for column in elt:
@@ -199,7 +199,7 @@ class Options(object):
         return '<Options for %s>' % self.object_name
 
     def __str__(self):
-        return "%s.%s" % (smart_str(self.app_label), smart_str(self.module_name))
+        return "%s.%s" % (smart_bytes(self.app_label), smart_bytes(self.module_name))
 
     def verbose_name_raw(self):
         """
@@ -209,7 +209,7 @@ class Options(object):
         """
         lang = get_language()
         deactivate_all()
-        raw = force_unicode(self.verbose_name)
+        raw = force_text(self.verbose_name)
         activate(lang)
         return raw
     verbose_name_raw = property(verbose_name_raw)
@@ -258,7 +258,7 @@ class Options(object):
             self._m2m_cache
         except AttributeError:
             self._fill_m2m_cache()
-        return self._m2m_cache.keys()
+        return list(self._m2m_cache)
     many_to_many = property(_many_to_many)
 
     def get_m2m_with_model(self):
@@ -269,7 +269,7 @@ class Options(object):
             self._m2m_cache
         except AttributeError:
             self._fill_m2m_cache()
-        return self._m2m_cache.items()
+        return list(six.iteritems(self._m2m_cache))
 
     def _fill_m2m_cache(self):
         cache = SortedDict()
@@ -326,8 +326,7 @@ class Options(object):
             cache = self._name_map
         except AttributeError:
             cache = self.init_name_map()
-        names = cache.keys()
-        names.sort()
+        names = sorted(cache.keys())
         # Internal-only names end with "+" (symmetrical m2m related names being
         # the main example). Trim them.
         return [val for val in names if not val.endswith('+')]
@@ -417,7 +416,7 @@ class Options(object):
             cache = self._fill_related_many_to_many_cache()
         if local_only:
             return [k for k, v in cache.items() if not v]
-        return cache.keys()
+        return list(cache)
 
     def get_all_related_m2m_objects_with_model(self):
         """
@@ -428,7 +427,7 @@ class Options(object):
             cache = self._related_many_to_many_cache
         except AttributeError:
             cache = self._fill_related_many_to_many_cache()
-        return cache.items()
+        return list(six.iteritems(cache))
 
     def _fill_related_many_to_many_cache(self):
         cache = SortedDict()
diff --git a/django/db/models/query.py b/django/db/models/query.py
index 8b6b42b7b1..e8d6ae2a7b 100644
--- a/django/db/models/query.py
+++ b/django/db/models/query.py
@@ -120,7 +120,7 @@ class QuerySet(object):
             if len(self._result_cache) <= pos:
                 self._fill_cache()
 
-    def __nonzero__(self):
+    def __bool__(self):
         if self._prefetch_related_lookups and not self._prefetch_done:
             # We need all the results in order to be able to do the prefetch
             # in one go. To minimize code duplication, we use the __len__
@@ -134,6 +134,7 @@ class QuerySet(object):
         except StopIteration:
             return False
         return True
+    __nonzero__ = __bool__ # Python 2
 
     def __contains__(self, val):
         # The 'in' operator works without this method, due to __iter__. This
@@ -245,8 +246,8 @@ class QuerySet(object):
             requested = None
         max_depth = self.query.max_depth
 
-        extra_select = self.query.extra_select.keys()
-        aggregate_select = self.query.aggregate_select.keys()
+        extra_select = list(self.query.extra_select)
+        aggregate_select = list(self.query.aggregate_select)
 
         only_load = self.query.get_loaded_field_names()
         if not fill_cache:
@@ -593,7 +594,7 @@ class QuerySet(object):
         flat = kwargs.pop('flat', False)
         if kwargs:
             raise TypeError('Unexpected keyword arguments to values_list: %s'
-                    % (kwargs.keys(),))
+                    % (list(kwargs),))
         if flat and len(fields) > 1:
             raise TypeError("'flat' is not valid when values_list is called with more than one field.")
         return self._clone(klass=ValuesListQuerySet, setup=True, flat=flat,
@@ -693,7 +694,7 @@ class QuerySet(object):
         depth = kwargs.pop('depth', 0)
         if kwargs:
             raise TypeError('Unexpected keyword arguments to select_related: %s'
-                    % (kwargs.keys(),))
+                    % (list(kwargs),))
         obj = self._clone()
         if fields:
             if depth:
@@ -751,7 +752,7 @@ class QuerySet(object):
 
         obj = self._clone()
 
-        obj._setup_aggregate_query(kwargs.keys())
+        obj._setup_aggregate_query(list(kwargs))
 
         # Add the aggregates to the query
         for (alias, aggregate_expr) in kwargs.items():
@@ -966,9 +967,9 @@ class ValuesQuerySet(QuerySet):
 
     def iterator(self):
         # Purge any extra columns that haven't been explicitly asked for
-        extra_names = self.query.extra_select.keys()
+        extra_names = list(self.query.extra_select)
         field_names = self.field_names
-        aggregate_names = self.query.aggregate_select.keys()
+        aggregate_names = list(self.query.aggregate_select)
 
         names = extra_names + field_names + aggregate_names
 
@@ -1097,9 +1098,9 @@ class ValuesListQuerySet(ValuesQuerySet):
             # When extra(select=...) or an annotation is involved, the extra
             # cols are always at the start of the row, and we need to reorder
             # the fields to match the order in self._fields.
-            extra_names = self.query.extra_select.keys()
+            extra_names = list(self.query.extra_select)
             field_names = self.field_names
-            aggregate_names = self.query.aggregate_select.keys()
+            aggregate_names = list(self.query.aggregate_select)
 
             names = extra_names + field_names + aggregate_names
 
@@ -1527,7 +1528,7 @@ class RawQuerySet(object):
             # Associate fields to values
             if skip:
                 model_init_kwargs = {}
-                for attname, pos in model_init_field_names.iteritems():
+                for attname, pos in six.iteritems(model_init_field_names):
                     model_init_kwargs[attname] = values[pos]
                 instance = model_cls(**model_init_kwargs)
             else:
diff --git a/django/db/models/query_utils.py b/django/db/models/query_utils.py
index 60bdb2bcb4..c1a690a524 100644
--- a/django/db/models/query_utils.py
+++ b/django/db/models/query_utils.py
@@ -8,6 +8,7 @@ circular import difficulties.
 from __future__ import unicode_literals
 
 from django.db.backends import util
+from django.utils import six
 from django.utils import tree
 
 
@@ -40,7 +41,7 @@ class Q(tree.Node):
     default = AND
 
     def __init__(self, *args, **kwargs):
-        super(Q, self).__init__(children=list(args) + kwargs.items())
+        super(Q, self).__init__(children=list(args) + list(six.iteritems(kwargs)))
 
     def _combine(self, other, conn):
         if not isinstance(other, Q):
@@ -114,7 +115,7 @@ class DeferredAttribute(object):
 
     def _check_parent_chain(self, instance, name):
         """
-        Check if the field value can be fetched from a parent field already 
+        Check if the field value can be fetched from a parent field already
         loaded in the instance. This can be done if the to-be fetched
         field is a primary key field.
         """
diff --git a/django/db/models/related.py b/django/db/models/related.py
index 90995d749f..a0dcec7132 100644
--- a/django/db/models/related.py
+++ b/django/db/models/related.py
@@ -1,4 +1,4 @@
-from django.utils.encoding import smart_unicode
+from django.utils.encoding import smart_text
 from django.db.models.fields import BLANK_CHOICE_DASH
 
 class BoundRelatedObject(object):
@@ -34,9 +34,9 @@ class RelatedObject(object):
         if limit_to_currently_related:
             queryset = queryset.complex_filter(
                 {'%s__isnull' % self.parent_model._meta.module_name: False})
-        lst = [(x._get_pk_val(), smart_unicode(x)) for x in queryset]
+        lst = [(x._get_pk_val(), smart_text(x)) for x in queryset]
         return first_choice + lst
-        
+
     def get_db_prep_lookup(self, lookup_type, value, connection, prepared=False):
         # Defer to the actual field definition for db prep
         return self.field.get_db_prep_lookup(lookup_type, value,
diff --git a/django/db/models/sql/compiler.py b/django/db/models/sql/compiler.py
index 7a0afa349d..1311ea546c 100644
--- a/django/db/models/sql/compiler.py
+++ b/django/db/models/sql/compiler.py
@@ -9,6 +9,7 @@ from django.db.models.sql.datastructures import EmptyResultSet
 from django.db.models.sql.expressions import SQLEvaluator
 from django.db.models.sql.query import get_order_dir, Query
 from django.db.utils import DatabaseError
+from django.utils import six
 
 
 class SQLCompiler(object):
@@ -82,7 +83,7 @@ class SQLCompiler(object):
         where, w_params = self.query.where.as_sql(qn=qn, connection=self.connection)
         having, h_params = self.query.having.as_sql(qn=qn, connection=self.connection)
         params = []
-        for val in self.query.extra_select.itervalues():
+        for val in six.itervalues(self.query.extra_select):
             params.extend(val[1])
 
         result = ['SELECT']
@@ -177,7 +178,7 @@ class SQLCompiler(object):
         """
         qn = self.quote_name_unless_alias
         qn2 = self.connection.ops.quote_name
-        result = ['(%s) AS %s' % (col[0], qn2(alias)) for alias, col in self.query.extra_select.iteritems()]
+        result = ['(%s) AS %s' % (col[0], qn2(alias)) for alias, col in six.iteritems(self.query.extra_select)]
         aliases = set(self.query.extra_select.keys())
         if with_aliases:
             col_aliases = aliases.copy()
@@ -553,7 +554,7 @@ class SQLCompiler(object):
             group_by = self.query.group_by or []
 
             extra_selects = []
-            for extra_select, extra_params in self.query.extra_select.itervalues():
+            for extra_select, extra_params in six.itervalues(self.query.extra_select):
                 extra_selects.append(extra_select)
                 params.extend(extra_params)
             cols = (group_by + self.query.select +
diff --git a/django/db/models/sql/query.py b/django/db/models/sql/query.py
index 53dad608bf..be257a5410 100644
--- a/django/db/models/sql/query.py
+++ b/django/db/models/sql/query.py
@@ -10,8 +10,9 @@ all about the internals of models in order to get the information it needs.
 import copy
 
 from django.utils.datastructures import SortedDict
-from django.utils.encoding import force_unicode
+from django.utils.encoding import force_text
 from django.utils.tree import Node
+from django.utils import six
 from django.db import connections, DEFAULT_DB_ALIAS
 from django.db.models import signals
 from django.db.models.expressions import ExpressionNode
@@ -602,22 +603,22 @@ class Query(object):
             # slight complexity here is handling fields that exist on parent
             # models.
             workset = {}
-            for model, values in seen.iteritems():
+            for model, values in six.iteritems(seen):
                 for field, m in model._meta.get_fields_with_model():
                     if field in values:
                         continue
                     add_to_dict(workset, m or model, field)
-            for model, values in must_include.iteritems():
+            for model, values in six.iteritems(must_include):
                 # If we haven't included a model in workset, we don't add the
                 # corresponding must_include fields for that model, since an
                 # empty set means "include all fields". That's why there's no
                 # "else" branch here.
                 if model in workset:
                     workset[model].update(values)
-            for model, values in workset.iteritems():
+            for model, values in six.iteritems(workset):
                 callback(target, model, values)
         else:
-            for model, values in must_include.iteritems():
+            for model, values in six.iteritems(must_include):
                 if model in seen:
                     seen[model].update(values)
                 else:
@@ -631,7 +632,7 @@ class Query(object):
             for model in orig_opts.get_parent_list():
                 if model not in seen:
                     seen[model] = set()
-            for model, values in seen.iteritems():
+            for model, values in six.iteritems(seen):
                 callback(target, model, values)
 
 
@@ -770,7 +771,7 @@ class Query(object):
         for k, aliases in self.join_map.items():
             aliases = tuple([change_map.get(a, a) for a in aliases])
             self.join_map[k] = aliases
-        for old_alias, new_alias in change_map.iteritems():
+        for old_alias, new_alias in six.iteritems(change_map):
             alias_data = self.alias_map[old_alias]
             alias_data = alias_data._replace(rhs_alias=new_alias)
             self.alias_refcount[new_alias] = self.alias_refcount[old_alias]
@@ -792,7 +793,7 @@ class Query(object):
                 self.included_inherited_models[key] = change_map[alias]
 
         # 3. Update any joins that refer to the old alias.
-        for alias, data in self.alias_map.iteritems():
+        for alias, data in six.iteritems(self.alias_map):
             lhs = data.lhs_alias
             if lhs in change_map:
                 data = data._replace(lhs_alias=change_map[lhs])
@@ -842,7 +843,7 @@ class Query(object):
         count. Note that after execution, the reference counts are zeroed, so
         tables added in compiler will not be seen by this method.
         """
-        return len([1 for count in self.alias_refcount.itervalues() if count])
+        return len([1 for count in six.itervalues(self.alias_refcount) if count])
 
     def join(self, connection, always_create=False, exclusions=(),
             promote=False, outer_if_first=False, nullable=False, reuse=None):
@@ -1302,7 +1303,7 @@ class Query(object):
                         field, model, direct, m2m = opts.get_field_by_name(f.name)
                         break
                 else:
-                    names = opts.get_all_field_names() + self.aggregate_select.keys()
+                    names = opts.get_all_field_names() + list(self.aggregate_select)
                     raise FieldError("Cannot resolve keyword %r into field. "
                             "Choices are: %s" % (name, ", ".join(names)))
 
@@ -1571,7 +1572,7 @@ class Query(object):
         # Tag.objects.exclude(parent__parent__name='t1'), a tag with no parent
         # would otherwise be overlooked).
         active_positions = [pos for (pos, count) in
-                enumerate(query.alias_refcount.itervalues()) if count]
+                enumerate(six.itervalues(query.alias_refcount)) if count]
         if active_positions[-1] > 1:
             self.add_filter(('%s__isnull' % prefix, False), negate=True,
                     trim=True, can_reuse=can_reuse)
@@ -1660,8 +1661,8 @@ class Query(object):
                 # from the model on which the lookup failed.
                 raise
             else:
-                names = sorted(opts.get_all_field_names() + self.extra.keys()
-                               + self.aggregate_select.keys())
+                names = sorted(opts.get_all_field_names() + list(self.extra)
+                               + list(self.aggregate_select))
                 raise FieldError("Cannot resolve keyword %r into field. "
                                  "Choices are: %s" % (name, ", ".join(names)))
         self.remove_inherited_models()
@@ -1775,7 +1776,7 @@ class Query(object):
             else:
                 param_iter = iter([])
             for name, entry in select.items():
-                entry = force_unicode(entry)
+                entry = force_text(entry)
                 entry_params = []
                 pos = entry.find("%s")
                 while pos != -1:
diff --git a/django/db/models/sql/subqueries.py b/django/db/models/sql/subqueries.py
index 7b92394e90..937505b9b0 100644
--- a/django/db/models/sql/subqueries.py
+++ b/django/db/models/sql/subqueries.py
@@ -10,7 +10,8 @@ from django.db.models.sql.query import Query
 from django.db.models.sql.where import AND, Constraint
 from django.utils.datastructures import SortedDict
 from django.utils.functional import Promise
-from django.utils.encoding import force_unicode
+from django.utils.encoding import force_text
+from django.utils import six
 
 
 __all__ = ['DeleteQuery', 'UpdateQuery', 'InsertQuery', 'DateQuery',
@@ -87,7 +88,7 @@ class UpdateQuery(Query):
         querysets.
         """
         values_seq = []
-        for name, val in values.iteritems():
+        for name, val in six.iteritems(values):
             field, model, direct, m2m = self.model._meta.get_field_by_name(name)
             if not direct or m2m:
                 raise FieldError('Cannot update model field %r (only non-relations and foreign keys permitted).' % field)
@@ -104,7 +105,7 @@ class UpdateQuery(Query):
         saving models.
         """
         # Check that no Promise object passes to the query. Refs #10498.
-        values_seq = [(value[0], value[1], force_unicode(value[2]))
+        values_seq = [(value[0], value[1], force_text(value[2]))
                       if isinstance(value[2], Promise) else value
                       for value in values_seq]
         self.values.extend(values_seq)
@@ -129,7 +130,7 @@ class UpdateQuery(Query):
         if not self.related_updates:
             return []
         result = []
-        for model, values in self.related_updates.iteritems():
+        for model, values in six.iteritems(self.related_updates):
             query = UpdateQuery(model)
             query.values = values
             if self.related_ids is not None:
@@ -170,7 +171,7 @@ class InsertQuery(Query):
             for obj in objs:
                 value = getattr(obj, field.attname)
                 if isinstance(value, Promise):
-                    setattr(obj, field.attname, force_unicode(value))
+                    setattr(obj, field.attname, force_text(value))
         self.objs = objs
         self.raw = raw