Remove dependency on django.utils.six for Django 3.0 support (#759)

storages/backends/apache_libcloud.py

@@ -9,8 +9,13 @@
 from django.core.files.base import File
 from django.core.files.storage import Storage
 from django.utils.deconstruct import deconstructible
-from django.utils.six import string_types
-from django.utils.six.moves.urllib.parse import urljoin
+
+try:
+    from django.utils.six import string_types
+    from django.utils.six.moves.urllib.parse import urljoin
+except ImportError:
+    string_types = str
+    from urllib.parse import urljoin
 
 try:
     from libcloud.storage.providers import get_driver

storages/backends/ftp.py

@@ -24,10 +24,14 @@
 from django.core.files.base import File
 from django.core.files.storage import Storage
 from django.utils.deconstruct import deconstructible
-from django.utils.six.moves.urllib import parse as urlparse
 
 from storages.utils import setting
 
+try:
+    from django.utils.six.moves.urllib import parse as urlparse
+except ImportError:
+    from urllib import parse as urlparse
+
 
 class FTPStorageException(Exception):
     pass

storages/backends/s3boto3.py

@@ -15,14 +15,19 @@
 from django.utils.encoding import (
     filepath_to_uri, force_bytes, force_text, smart_text,
 )
-from django.utils.six.moves.urllib import parse as urlparse
 from django.utils.timezone import is_naive, make_naive
 
 from storages.utils import (
     check_location, get_available_overwrite_name, lookup_env, safe_join,
     setting,
 )
 
+try:
+    from django.utils.six.moves.urllib import parse as urlparse
+except ImportError:
+    from urllib import parse as urlparse
+
+
 try:
     import boto3.session
     from boto3 import __version__ as boto3_version

storages/backends/sftpstorage.py

@@ -16,10 +16,14 @@
 from django.core.files.base import File
 from django.core.files.storage import Storage
 from django.utils.deconstruct import deconstructible
-from django.utils.six.moves.urllib import parse as urlparse
 
 from storages.utils import setting
 
+try:
+    from django.utils.six.moves.urllib import parse as urlparse
+except ImportError:
+    from urllib import parse as urlparse
+
 
 @deconstructible
 class SFTPStorage(Storage):

tests/test_s3boto.py

@@ -12,10 +12,14 @@
 from django.core.files.base import ContentFile
 from django.test import TestCase
 from django.utils import timezone as tz
-from django.utils.six.moves.urllib import parse as urlparse
 
 from storages.backends import s3boto
 
+try:
+    from django.utils.six.moves.urllib import parse as urlparse
+except ImportError:
+    from urllib import parse as urlparse
+
 
 class S3BotoTestCase(TestCase):
     @mock.patch('storages.backends.s3boto.S3Connection')

tests/test_s3boto3.py

@@ -13,11 +13,16 @@
 from django.core.exceptions import ImproperlyConfigured
 from django.core.files.base import ContentFile
 from django.test import TestCase, override_settings
-from django.utils.six.moves.urllib import parse as urlparse
 from django.utils.timezone import is_aware, utc
 
 from storages.backends import s3boto3
 
+try:
+    from django.utils.six.moves.urllib import parse as urlparse
+except ImportError:
+    from urllib import parse as urlparse
+
+
 try:
     from unittest import mock
 except ImportError:  # Python 3.2 and below