code: def main(argv: Sequence[str]) -> Optional[dev_server.LitServerType]:
      if len(argv) > 1:
          raise app.UsageError("Too many command-line arguments.")
  
      assert _MODEL_PATH.value, "Must specify --model_path to run."
  
      if _DO_TRAIN.value:
          train(_MODEL_PATH.value)
  
      if _DO_SERVE.value:
          return run_server(_MODEL_PATH.value)
  
imports: from collections.abc import Sequence
  import os
  import sys
  from typing import Optional
  from absl import app
  from absl import flags
  from absl import logging
  from lit_nlp import dev_server
  from lit_nlp import server_flags
  from lit_nlp.api import dataset
  from lit_nlp.api import dtypes
  from lit_nlp.api import layout
  from lit_nlp.api import types
  from lit_nlp.examples.coref import edge_predictor
  from lit_nlp.examples.coref import encoders
  from lit_nlp.examples.coref import model
  from lit_nlp.examples.coref.datasets import ontonotes
  from lit_nlp.examples.coref.datasets import winogender
  from lit_nlp.lib import file_cache
  from lit_nlp.lib import utils
label_desc: Use image node_id 5 for calling a global function with example usage: main(argv) and returns: run_server