docs: def add_to_following(self, following):
          """
          :calls: `PUT /user/following/:user <http://developer.github.com/v3/users/followers>`_
          :param following: :class:`github.NamedUser.NamedUser`
          :rtype: None
          """
          assert isinstance(following, github.NamedUser.NamedUser), following
          headers, data = self._requester.requestJsonAndCheck(
              "PUT",
              "/user/following/" + following._identity
          )