code: def _get_expert_parallel_src_rank(group_name):
      """Calculate the global rank corresponding to a local rank zero
      in the expert parallel group."""
      global_rank = dist.get_rank()
      local_world_size = _get_expert_parallel_world_size(group_name)
      return (global_rank // local_world_size) * local_world_size
  
imports: from deepspeed import comm
  from deepspeed.utils import log_dist
  from deepspeed.utils.exceptions import DeprecatedException
label_desc: Use image node_id 21 for calling a global function with example usage: _get_expert_parallel_src_rank(group_name) and returns: unknown