code: def branches(self):
          # type: () -> List[str]
          
          if self._branches is None:
              cmd = 'git branch --contains {}'.format(self.sha1)
              out = shell.run(
                  cmd,
                  capture=True,
                  never_pretend=True
              ).stdout.strip()
              self._branches = [x.strip('* \t\n') for x in out.splitlines()]
  
          return self._branches
docs: List of all branches this commit is a part of.