title: git create local branch for a forked upstream tag
body: <p>I've been trying to find a way to create a local branch that starts from a tag on an upstream repo I've forked and haven't found anything that helps.</p>
  
  <p>I have the upstream master on a master branch locally but I'm not sure what I need to do to branch the upstream tag.</p>
  
  <p>I've tried:</p>
  
  <pre><code>git branch upstream/master tagname
  git branch master tagname
  git branch upstream tagname
  </code></pre>
  
  <p>and none of those worked. Thanks.</p>