code: def build_datamodule(dataset_key) -> pl.LightningDataModule:
      dataset_builder = registry.get_builder_class(dataset_key)
      assert dataset_builder, (
          f"Key {dataset_key} doesn't have a registered "
          + "dataset builder"
      )
      builder_instance: pl.LightningDataModule = dataset_builder()
      return builder_instance
  
imports: import logging
  import os
  import warnings
  from enum import Enum
  from typing import Any, Dict, List, Optional, Tuple, Union
  import mmf
  import pytorch_lightning
  import torch
  from mmf.common.meter import Meter
  from mmf.common.registry import registry
  from mmf.datasets.iteration_strategies import ConstantIterationStrategy, IterationStrategy, SizeProportionalIterationStrategy
  from mmf.datasets.processors.processors import Processor
  from mmf.utils.configuration import Configuration, get_global_config
  from mmf.utils.distributed import is_dist_initialized, is_main, is_xla, synchronize
  from mmf.utils.general import get_optimizer_parameters
  from omegaconf import DictConfig, OmegaConf
  from packaging import version
label_desc: Use image node_id 7 for calling a global function with example usage: build_datamodule(dataset_key) and returns: builder_instance