title: Multiple shebangs to work for different OS
body: <p>Is there a way I can have multiple shebangs?</p>
  
  <p>So I can call <code>#!/usr/bin/env python3</code> on Ubuntu, but MacOS doesn't seem to have an equivalent, and I would like to call <code>#!/usr/bin/python3</code> instead on it.</p>
  
  <p>So is it possible to do something like:</p>
  
  <pre><code>#!/usr/bin/env python3
  #!/usr/bin/python3
  </code></pre>