title: PROJECT_ROOT = os.path.dirname(__file__) error
body: <p>When i try:<br>
  <code>PROJECT_ROOT = os.path.dirname(__file__)</code><br>
  i get error like this:<br>
  <code>Traceback (most recent call last):<br>
  File "&lt; stdin&gt;", line 1, in &lt;module&gt;<br>
  NameError: name '__file__' is not defined</code></p>
  
  <p>Does someone know how to fix this?</p>