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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def assigned(self, user, include=None):
 """ Retrieve the assigned tickets for this user. :param include: list of objects to sideload. `Side-loading API Docs <https://developer.zendesk.com/rest_api/docs/core/side_loading>`__. :param user: User object or id """

        return self._query_zendesk(self.endpoint.assigned, 'ticket', id=user, include=include)