def METHOD_NAME(self):
    self.dataplane = ptf.dataplane_instance
    self.router_mac = self.test_params['router_mac']
    ptf_test_port_map = self.test_params['ptf_test_port_map']
    with open(ptf_test_port_map) as f:
        self.ptf_test_port_map = json.load(f)
    self.src_ports = self.ptf_test_port_map['ptf_src_ports']
    self._vlan_dict = self.ptf_test_port_map['vlan_ip_port_pair']