docs: def list_deploy_keys(self, auth, username, repo_name):
          """
          List deploy keys for the specified repo.
  
          :param auth.Authentication auth: authentication object
          :param str username: username of owner of repository
          :param str repo_name: the name of the repo
          :return: a list of deploy keys for the repo
          :rtype: List[GogsRepo.DeployKey]
          :raises NetworkFailure: if there is an error communicating with the server
          :raises ApiFailure: if the request cannot be serviced
          """
          response = self.get("/repos/{u}/{r}/keys".format(u=username, r=repo_name), auth=auth)
          return [GogsRepo.DeployKey.from_json(key_json) for key_json in response.json()]