Add test for python_venv language

testing/resources/python3_hooks_repo/py3_hook.py

@@ -3,7 +3,7 @@ from __future__ import print_function
 import sys
 
 
-def func():
+def main():
     print(sys.version_info[0])
     print(repr(sys.argv[1:]))
     print('Hello World')

testing/resources/python3_hooks_repo/setup.py

@@ -1,11 +1,8 @@
-from setuptools import find_packages
 from setuptools import setup
 
 setup(
     name='python3_hook',
     version='0.0.0',
-    packages=find_packages('.'),
-    entry_points={
-        'console_scripts': ['python3-hook = python3_hook.main:func'],
-    },
+    py_modules=['py3_hook'],
+    entry_points={'console_scripts': ['python3-hook = py3_hook:main']},
 )