<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def organization_memberships(self, user):
 """ Retrieve the organization memberships for this user. :param user: User object or id """

        return self._query_zendesk(self.endpoint.organization_memberships, 'organization_membership', id=user)