def get_membership(self, user, membership_type):
from canvasapi.user import User<EOL>user_id = obj_or_id(user, "<STR_LIT:user>", (User,))<EOL>response = self._requester.request(<EOL>'<STR_LIT:GET>',<EOL>'<STR_LIT>'.format(self.id, membership_type, user_id)<EOL>)<EOL>return GroupMembership(self._requester, response.json())<EOL>
List users in a group.

:calls: `GET /api/v1/groups/:group_id/users/:user_id \
    <https://canvas.instructure.com/doc/api/groups.html#method.group_memberships.show>`_

    or `GET /api/v1/groups/:group_id/memberships/:membership_id
    <https://canvas.instructure.com/doc/api/groups.html#method.group_memberships.show>`_

:param user: list of user ids
:type user: :class:`canvasapi.user.User` or int

:rtype: :class:`canvasapi.group.GroupMembership`