add Django 3.0 to the test matrix

.travis.yml

@@ -35,6 +35,8 @@ matrix:
       env: DJANGO=2.1
     - python: 3.6
       env: DJANGO=2.2
+    - python: 3.6
+      env: DJANGO=3.0
     - python: 3.6
       env: DJANGO=master
 
@@ -46,6 +48,8 @@ matrix:
       env: DJANGO=2.1
     - python: 3.7
       env: DJANGO=2.2
+    - python: 3.7
+      env: DJANGO=3.0
     - python: 3.7
       env: DJANGO=master
 

graphene_django/debug/sql/tracking.py

@@ -5,7 +5,7 @@
 from threading import local
 from time import time
 
-from django.utils import six
+import six
 from django.utils.encoding import force_text
 
 from .types import DjangoDebugSQL

graphene_django/settings.py

@@ -13,9 +13,9 @@
 """
 from __future__ import unicode_literals
 
+import six
 from django.conf import settings
 from django.test.signals import setting_changed
-from django.utils import six
 
 try:
     import importlib  # Available in Python 3.1+

graphene_django/utils/utils.py

@@ -1,8 +1,8 @@
 import inspect
 
+import six
 from django.db import models
 from django.db.models.manager import Manager
-from django.utils import six
 from django.utils.encoding import force_text
 from django.utils.functional import Promise
 

tox.ini

@@ -1,6 +1,7 @@
 [tox]
 envlist =
     py{27,35,36,37}-django{111,20,21,22,master},
+    py{36,37}-django30,
     black,flake8
 
 [travis:env]
@@ -9,6 +10,7 @@ DJANGO =
     2.0: django20
     2.1: django21
     2.2: django22
+    3.0: django30
     master: djangomaster
 
 [testenv]
@@ -23,6 +25,7 @@ deps =
     django20: Django>=2.0,<2.1
     django21: Django>=2.1,<2.2
     django22: Django>=2.2,<3.0
+    django30: Django>=3.0a1,<3.1
     djangomaster: https://github.com/django/django/archive/master.zip
 commands = {posargs:py.test --cov=graphene_django graphene_django examples}