diff --git a/setup.cfg b/setup.cfg
index 0d89aba..3fdf3d3 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -8,4 +8,4 @@ test=pytest
 
 [tool:pytest]
 # Make sure we only include those files suffixed with -tests
-python_files = tests/*_tests.py
+python_files = tests/test_*.py
diff --git a/tests/di_tests.py b/tests/test_di.py
similarity index 99%
rename from tests/di_tests.py
rename to tests/test_di.py
index 18a7ae4..6815d8a 100644
--- a/tests/di_tests.py
+++ b/tests/test_di.py
@@ -12,10 +12,11 @@
 
 from di import injector, Key, DependencyMap, ContextualDependencyMap, PatchedDependencyMap, MetaInject
 
-PY3 = sys.version_info[0] >= 3
+PY3 = sys.hexversion >= 0x03000000
+PY35 = sys.hexversion >= 0x03050000
 
-# Import tests using Python3 syntax
-if PY3:
+# Import tests using Python3 syntax when >=3.5
+if PY35:
     from .py3 import *