title: How do I get a list of changesets between two revisions using the internal Mercurial API?
body: <p>I want to check the user names in a pre-commit-hook. From the command line, what I want to achieve looks like this:</p>
  
  <pre><code>hg log -r "$HG_NODE:tip" --template "{author}\n"
  </code></pre>
  
  <p>How do I achieve the same using the internal Mercurial API?</p>