Fix pycodestyle, experiment with custom buildpack

PyRIGS/tests/test_unit.py

@@ -129,7 +129,6 @@ class TestSampleDataGenerator(TestCase):
         assert response.status_code == 403
         self.client.logout()
 
-
     def test_keyholder_access(self):
         assert self.client.login(username="keyholder", password="keyholder")
 

app.json

@@ -51,7 +51,7 @@
       "url": "heroku/nodejs"
     },
     {
-      "url": "heroku/python"
+      "url": "https://github.com/nottinghamtec/heroku-buildpack-python"
     }
   ]
 }