title: Avoid .pyc Files in Python 3.x?
body: <p>Currently, I'm working with Python 3.4. How could I avoid <code>.pyc</code> or <code>.pyo</code> files (<code>__pycache__</code>) without editing the commandline?</p>
  
  <p>The following command works perfectly
  Using terminal: <code>python3 -B something.py</code></p>
  
  <p>But these are not working in Python 3 (or are they??):</p>
  
  <pre><code>import os
  
  os.environ['PYTHONDONTWRITEBYTECODE'] = "whatever"
  </code></pre>
  
  <p>according to the <a href="https://docs.python.org/3.4/using/cmdline.html#envvar-PYTHONDONTWRITEBYTECODE" rel="nofollow">instructions</a>, if it is set to a non-empty string, it should work. But I couldn't.</p>
  
  <p>What am I missing?</p>