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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 add_multiple(self, *users):
 """Add multiple users to the group at once. Each given user must be a dictionary containing a nickname and either an email, phone number, or user_id. :param args users: the users to add :return: a membership request :rtype: :class:`MembershipRequest` """

        guid = uuid.uuid4()
        for i, user_ in enumerate(users):
            user_['guid'] = '{}-{}'.format(guid, i)

        payload = {'members': users}
        url = utils.urljoin(self.url, 'add')
        response = self.session.post(url, json=payload)
        return MembershipRequest(self, *users, group_id=self.group_id,
                                 **response.data)