title: Unable to access Heroku config vars from Django settings.py
body: <p>I have some config vars set on Heroku as described here: <a href="https://devcenter.heroku.com/articles/config-vars" rel="nofollow">https://devcenter.heroku.com/articles/config-vars</a>. 
  When I run:</p>
  
  <pre><code>heroku config
  </code></pre>
  
  <p>I see the config var in the list:</p>
  
  <pre><code>COMPRESS_OFFLINE:                  True
  </code></pre>
  
  <p>and I can run</p>
  
  <pre><code>heroku config:get COMPRESS_OFFLINE
  </code></pre>
  
  <p>and I get: </p>
  
  <pre><code>True
  </code></pre>
  
  <p>In my Django settings.py, I have:</p>
  
  <pre><code>import os
  COMPRESS_OFFLINE = os.environ['COMPRESS_OFFLINE']
  </code></pre>
  
  <p>This is how the article linked above tells you to access Heroku config variables in Django. I have this config var set in my local .env file, and I can run foreman locally. But, when I deploy to Heroku, I get this error during deploy:</p>
  
  <pre><code>KeyError: 'COMPRESS_OFFLINE'
  !     Push rejected, failed to compile Python app
  </code></pre>
  
  <p>I have the feeling I'm missing something painfully obvious, any suggestions? </p>