title: Jupyter reports "bad interpreter" following Homebrew Python update
body: <p>Since updating my Python using Homebrew</p>
  
  <pre><code>jupyter --version
  </code></pre>
  
  <p>gives</p>
  
  <pre><code>-bash: /usr/local/bin/jupyter: /usr/local/opt/python/bin/python2.7: bad interpreter: No such file or directory
  </code></pre>
  
  <p>which makes some sense, since there's no longer a Python at <code>/usr/local/.../python2.7</code>. But I don't see any way to repair this. </p>
  
  <p>Prior to updating Python, I there was a Python there, and the Homebrew's symlinked <code>python</code> pointed there, but now <code>which -a python</code> gives</p>
  
  <pre><code>/usr/local/opt/python@2/libexec/bin/python
  /usr/local/bin/python
  /usr/bin/python
  </code></pre>
  
  <p>which corresponds to what I want, and are, respectively</p>
  
  <ul>
  <li>Homebrew's 2.7, which is found because it is on <code>PATH</code></li>
  <li>Homebrew's symlinked 3.6.x</li>
  <li>Apple's old Python</li>
  </ul>
  
  <p>I've also <code>brew link --overwrite --force python2</code> <a href="https://stackoverflow.com/a/49099773/656912">for good measure</a>, but this has no effect.</p>
  
  <p>How do I get <code>jupyter</code> to find and use the Python 2.7 on my <code>PATH</code>?</p>