title: Determining the issue regarding python versions for running repo init
body: <p>When I am using <code>repo init</code> to initialize some repo from a source, I keep getting:</p>
  <pre><code>Traceback (most recent call last):
    File &quot;/home/workspace/.repo/repo/main.py&quot;, line 56, in &lt;module&gt;
      from subcmds.version import Version
    File &quot;/home/workspace/.repo/repo/subcmds/__init__.py&quot;, line 38, in &lt;module&gt;
      ['%s' % name])
    File &quot;/home/workspace/.repo/repo/subcmds/upload.py&quot;, line 27, in &lt;module&gt;
      from hooks import RepoHook
    File &quot;/home/workspace/.repo/repo/hooks.py&quot;, line 472
      file=sys.stderr)
          ^
  SyntaxError: invalid syntax
  
  </code></pre>
  <p>The following are the python versions I have:</p>
  <pre><code>python -V -&gt; 2.7
  python3 -V -&gt; 3.6
  </code></pre>
  <p>According to <a href="https://github.com/Iolaum/git-repo/blob/e7379dc5f75f4c331c16b4199904dc98ee858e5f/docs/python-support.md" rel="nofollow noreferrer">this</a> link, python 3.6 is required starting with repo-1.14 but I'm not certain if that's what my repo version is - didn't have any luck finding a way around determining the version.</p>