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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 get_all_users(self, nid=None):
 """Get a listing of data for each user in a network `nid` :type nid: str :param nid: This is the ID of the network to get users from. This is optional and only to override the existing `network_id` entered when created the class :returns: Python object containing returned data, a list of dicts containing user data. """

        r = self.request(
            method="network.get_all_users",
            nid=nid
        )
        return self._handle_error(r, "Could not get users.")