docs: def create_key(self, title, key):
          """
          :calls: `POST /user/keys <http://developer.github.com/v3/users/keys>`_
          :param title: string
          :param key: string
          :rtype: :class:`github.UserKey.UserKey`
          """
          assert isinstance(title, (str, unicode)), title
          assert isinstance(key, (str, unicode)), key
          post_parameters = {
              "title": title,
              "key": key,
          }
          headers, data = self._requester.requestJsonAndCheck(
              "POST",
              "/user/keys",
              input=post_parameters
          )
          return github.UserKey.UserKey(self._requester, headers, data, completed=True)