title: Shell is selecting Python 2.7, but not 3.7
body: <p>I have <code>Python 3.7</code> and I had a <code>Python 2.7.</code> </p>
  
  <p>But when I am using Python Launcher it uses 2.7 not 3.7. </p>
  
  <p>How to use <code>Python 3.7</code>? OS - Mac OS.</p>