title: Static Root and Static Url confusion in Django
body: <p>I am trying to read create mp3 files in django. but I am confused about static and static_root that I have configured. 
  WHat happening is that in my code at a point when I print the below line it shows <br>
  <strong>/usr/local/src/mena_recording/play/static/audio/dorris_0_.mp3</strong></p>
  
  <p>code:</p>
  
  <pre><code>print settings.BASE_DIR+'/play/static/audio/'+record.driverName +'_'+str(counter)+'_'+ '.mp3'
  </code></pre>
  
  <p>but when I use the same thing in the next line in this piece it gives this error:</p>
  
  <pre><code>IOError at /
  [Errno 2] No such file or directory: u'/usr/local/src/mena_recording/play/static_root/play/static/audio/dorris_0_.oga'
  </code></pre>
  
  <p>code:</p>
  
  <pre><code>with open(settings.BASE_DIR+'/play/static/audio/'+record.driverName +'_'+str(counter)+'_'+ '.mp3', 'w') as mp3_file:
      mp3_file.write(decoded_mp3_str)
      mp3_file.close()
  </code></pre>
  
  <p><strong>my settings.py</strong></p>
  
  <pre><code>STATIC_ROOT = os.path.join(BASE_DIR, 'play/static_root')
  STATIC_URL = '/static/'
  
  STATICFILES_DIRS = (
      os.path.join(BASE_DIR, 'mena_recording/static'),
      os.path.join(BASE_DIR, 'play/static'),
      # Put strings here, like "/home/html/static" or "C:/www/django/static".
      # Always use forward slashes, even on Windows.
      # Don't forget to use absolute paths, not relative paths.
  )
  </code></pre>
  
  <p>Would someone enlighten me please how this works ?</p>
  
  <p>Thank you.</p>