title: Gunicorn doesn't work
body: <p>I'm trying to deploy my django app on heroku. After following the steps instructed by the official document, the dyno I launched always crashes. Then I went through the whole process, and I think the problem might lie on the gunicorn part. 
  Following the instruction, I set the Procfile as 'web: unicorn hellodjango.wsgi', and when I $foreman start, it only shows "21:21:07 web.1  | started with pid 77969". It didn't say where the web is launched. 
  Then I tried to test whether gunicorn is working well. So I tried: "$gunicorn hellodjango.wsgi:application", it indeed doesn't work. </p>
  
  <p>I think the path is correct because in current folder there's a hellodjango folder and inside there's the file wsgi.py. </p>
  
  <p>What might be the problem?</p>