--- a/setup.py
+++ b/setup.py
@@ -2,11 +2,8 @@
 from setuptools import setup
 
 packages = \
-['niaclass', 'niaclass.tests']
+['niaclass']
 
-package_data = \
-{'': ['*'], 'niaclass.tests': ['test_files/*']}
-
 install_requires = \
 ['NiaPy>=2.0.0rc17,<3.0.0',
  'numpy>=1.20.0,<2.0.0',
@@ -24,7 +21,6 @@
     'maintainer_email': None,
     'url': 'https://github.com/lukapecnik/NiaClass',
     'packages': packages,
-    'package_data': package_data,
     'install_requires': install_requires,
     'python_requires': '>=3.7.1,<4.0.0',
 }