diff --git a/setup.cfg b/setup.cfg
index 1808227..0114591 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -6,7 +6,7 @@ author = Bruno Renié
 description = A simple yet powerful CloudStack API client for Python and the command-line.
 long_description = file: README.rst
 license = BSD
-license_file = LICENSE
+license_files = LICENSE
 classifiers =
     Intended Audience :: Developers
     Intended Audience :: System Administrators
diff --git a/tests.py b/tests.py
index 7ce644f..ea18bab 100644
--- a/tests.py
+++ b/tests.py
@@ -154,7 +154,6 @@ def test_env_var_combined_with_dir_config(self):
                     "trace": None,
                     "poll_interval": 2.0,
                     "name": "hanibal",
-                    "poll_interval": 2.0,
                     "verify": None,
                     "dangerous_no_tls_verify": True,
                     "retry": 0,
@@ -194,7 +193,6 @@ def test_current_dir_config(self):
                     "trace": None,
                     "poll_interval": 2.0,
                     "name": "cloudstack",
-                    "poll_interval": 2.0,
                     "verify": None,
                     "dangerous_no_tls_verify": True,
                     "retry": 0,
diff --git a/tox.ini b/tox.ini
index ddc3d88..f3f218b 100644
--- a/tox.ini
+++ b/tox.ini
@@ -18,6 +18,7 @@ deps=
 	flake8-import-order
 commands =
 	pip install pytest pytest-cache pytest-cov
-	python setup.py test
+	pip wheel --no-deps -w dist .
+	test: pytest -v
 	check-manifest
 	lint: flake8 cs tests.py