title: How to detect if module is installed in "editable mode"?
body: <p>I'm pip-installing my module like so:</p>
  
  <pre><code>cd my_working_dir
  pip install -e .
  </code></pre>
  
  <p>When I later import the module from within Python, can I somehow detect if the module is installed in this editable mode?</p>
  
  <p>Right now, I'm just checking if there's a .git folder in <code>os.path.dirname(mymodule.__file__))</code> which, well, only works if there's actually a .git folder there. Is there a more reliable way?</p>