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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 modify_fw_device(self, tenant_id, fw_id, data):
 """Modifies the firewall cfg. """

        drvr_dict, mgmt_ip = self.sched_obj.get_fw_dev_map(fw_id)
        return drvr_dict.get('drvr_obj').modify_fw(tenant_id, data)