Fixed pytest

.travis.yml

@@ -22,7 +22,7 @@ before_install:
 install:
 - |
   if [ "$TEST_TYPE" = build ]; then
-    pip install pytest pytest-cov pytest-benchmark coveralls six pytest-django mock django-filter
+    pip install pytest==3.0.2 pytest-cov pytest-benchmark coveralls six pytest-django mock django-filter
     pip install -e .
     python setup.py develop
   elif [ "$TEST_TYPE" = lint ]; then

setup.py

@@ -41,7 +41,7 @@ setup(
     ],
     tests_require=[
         'django-filter>=0.10.0',
-        'pytest>=3.0',
+        'pytest',
         'pytest-django',
         'mock',
         # Required for Django postgres fields testing