class_docstr: A router to get the worker based on the partition ID.
code: def get_to_worker(self, partition_idx: int) -> str:
      rpc_worker_list = self.partition_to_workers[partition_idx]
      worker_idx = self.rpc_worker_indices[partition_idx]
      router_worker = rpc_worker_list[worker_idx]
      self.rpc_worker_indices[partition_idx] = (worker_idx + 1) % len(
          rpc_worker_list
      )
      return router_worker
  
imports: import logging
  import threading
  from abc import ABC, abstractmethod
  from typing import Any, Callable, Dict, List, Optional
  from torch.distributed import rpc
  from torch_geometric.distributed.dist_context import DistContext, DistRole
label_desc: Use image node_id 2 for calling the RPCRouter obj's underlying member method code with example usage: obj.get_to_worker(partition_idx) and returns: router_worker