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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 put_contacts(self, uid, **kwargs):
 """ Assign contacts to the specified list. :Example: client.lists.put_contacts(uid=1901010, contacts="1723812,1239912") :param int uid: The unique id of the List. Required. :param str contacts: Contact ID(s), separated by comma. Required. """

        return self.update_subresource_instance(uid,
                                                body=kwargs,
                                                subresource=None,
                                                slug="contacts")