title: Copy system lib files in python venv
body: <p>I'm trying to be really hacky and edit a system library file normally found inside <code>/usr/lib/python/</code> for a project I'm working on. </p>
  
  <p>Obviously, I don't want to edit the actual file (and indeed I'd have to first make it <code>rw</code> as it's currently readonly).</p>
  
  <p>Is there a way to tell python, when making a new virtualenv, to make copies of the existing system libraries and use those, so that I can safely edit them without breaking everything else that might be trying to use those files?</p>
  
  <p>I've been creating the virtualenvs with</p>
  
  <pre><code>python3.7 -m venv myVenvName
  </code></pre>