code: def _iter_stage_metrics_names(stage, dvc_config):
      stage_metrics = _stage_metrics(_stage_config(stage, dvc_config))
      for x in stage_metrics:
          if isinstance(x, str):
              yield x
          elif isinstance(x, dict):
              for name in x:
                  yield name
          else:
              log.warning(
                  "unexpected metrics value %r for stage '%s', skipping",
                  x,
                  stage,
              )
  
imports: import json
  import logging
  import os
  import subprocess
  import yaml
  from guild import util
  from guild import var
label_desc: Use image node_id 34 for calling a global function with example usage: _iter_stage_metrics_names(stage, dvc_config) without return types