[black] paint it black & add tox target

setup.py

@@ -26,7 +26,7 @@ requirements = ["python-gitlab", "pyyaml", "pandas", "boto3"]
 setup_requirements = []
 test_requirements = []
 
-with open('README.rst') as fobj:
+with open("README.rst") as fobj:
     long_description = fobj.read()
 
 

tox.ini

@@ -16,3 +16,11 @@ skip_install = true
 deps =
   black
 commands = black --check .
+
+[testenv:black-run]
+basepython = python3
+skip_install = true
+deps =
+  black
+commands = black .
+