docs: def _remote_github_url_to_string(remote_url):
      """Parse out the repository identifier from a github URL."""
      # TODO: make this work with https URLs
      match = re.search('git@github\.com:(.*)\.git', remote_url)
      if not match:
          raise EnvironmentError('Remote is not a valid github URL')
      identifier = match.group(1)
      return re.sub('\W', ':', identifier)