code: def main(
      rng: jnp.ndarray,
      config: ml_collections.ConfigDict,
      workdir: str,
      writer: metric_writers.MetricWriter,
  ) -> None:
      """Main function for Scenic."""
  
      model_cls = models.get_model_cls(config.model_name)
      data_rng, rng = jax.random.split(rng)
  
      if config.checkpoint:
          # When restoring from a checkpoint, change the dataset seed to ensure that
          # the example order is new. With deterministic data, this ensures enough
          # randomization and in the future with deterministic data + random access,
          # we can feed the global step to the dataset loader to always continue
          # reading the rest of the data if we resume a job that was interrupted.
          checkpoint_path = checkpoints.latest_checkpoint(workdir)
          logging.info("CHECKPOINT PATH: %s", checkpoint_path)
          if checkpoint_path is not None:
              global_step = (
                  train_utils.checkpoint_path_step(checkpoint_path) or 0
              )
              logging.info(
                  "Folding global_step %s into dataset seed.",
                  global_step,
              )
              data_rng = jax.random.fold_in(data_rng, global_step)
  
      dataset = train_utils.get_dataset(
          config,
          data_rng,
          dataset_service_address=FLAGS.dataset_service_address,
      )
  
      trainers.get_trainer(config.trainer_name)(
          rng=rng,
          config=config,
          model_cls=model_cls,
          dataset=dataset,
          workdir=workdir,
          writer=writer,
      )
  
file_path: scenic/scenic/main.py
imports: from absl import flags
  from absl import logging
  from clu import metric_writers
  from flax.training import checkpoints
  import jax
  import jax.numpy
  import ml_collections
  from scenic import app
  from scenic.model_lib import models
  from scenic.train_lib import train_utils
  from scenic.train_lib import trainers
label_desc: Use image node_id 1 for calling a global function with example usage: main(rng, config, workdir, writer) without return types