code: def init_method(self):
      use_tcp_init = os.environ.get("RPC_INIT_WITH_TCP", None)
      if use_tcp_init == "1":
          master_addr = os.environ["MASTER_ADDR"]
          master_port = os.environ["MASTER_PORT"]
          return f"tcp://{master_addr}:{master_port}"
      else:
          return self.file_init_method
  
file_path: pytorch/torch/testing/_internal/distributed/rpc/rpc_agent_test_fixture.py
imports: import os
  from abc import ABC, abstractmethod
  import torch.testing._internal.dist_utils
label_desc: Use image node_id 2 for calling the RpcAgentTestFixture obj's underlying member method code with example usage: obj.init_method() and returns: str, master_addr, str, master_port, self