fixes wrong import

Author: saxix

src/concurrency/compat.py

@@ -1,10 +1,18 @@
 # -*- coding: utf-8 -*-
 from __future__ import absolute_import, print_function, unicode_literals
 
-# from django.core.urlresolvers import get_callable
-# from django.db.transaction import atomic
-
 try:
     from django.template.base import TemplateDoesNotExist
 except ImportError:
     from django.template.exceptions import TemplateDoesNotExist  # noqa - django 1.9
+
+# try:
+#     from django.db.transaction import atomic
+# except ImportError:
+#     from django.db.transaction import commit_on_success as atomic  # noqa
+#
+
+try:
+    from django.urls.utils import get_callable
+except ImportError:
+    from django.core.urlresolvers import get_callable

src/concurrency/config.py

@@ -3,9 +3,10 @@
 
 from django.core.exceptions import ImproperlyConfigured
 from django.test.signals import setting_changed
-from django.urls import get_callable
 from django.utils import six
 
+from .compat import get_callable
+
 # List Editable Policy
 # 0 do not save updated records, save others, show message to the user
 # 1 abort whole transaction

src/concurrency/triggers.py

@@ -7,6 +7,7 @@
 from django.db import connections, router
 from django.db.utils import DatabaseError
 
+from .fields import _TRIGGERS  # noqa
 
 def get_trigger_name(field):
     """