I had such problem when try to deploy my app on Heroku:
Warning: Your application is missing a Procfile. This file tells Heroku how to run your application.
and
remote: -----> Installing python-2.7.13
despite the fact I use 3.5.2 python version in my virtualenv.
I had already checked that Procfile is in the root directory, doen't have .txt extension and have been commited. How can I fix it? Help, please