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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 hosting_devices_unassigned_from_cfg_agent(self, context, payload):
 """Deal with hosting devices unassigned from this config agent."""

        try:
            if payload['hosting_device_ids']:
                #TODO(hareeshp): implement unassignment of hosting devices
                pass
        except KeyError as e:
            LOG.error("Invalid payload format for received RPC message "
                      "`hosting_devices_unassigned_from_cfg_agent`. Error "
                      "is %(error)s. Payload is %(payload)s",
                      {'error': e, 'payload': payload})