code: def _tf2_callback():
      global FixedLengthRecordDataset, TFRecordDataset, TextLineDataset
      if tf2.enabled():
          FixedLengthRecordDataset = FixedLengthRecordDatasetV2
          TFRecordDataset = TFRecordDatasetV2
          TextLineDataset = TextLineDatasetV2
      else:
          FixedLengthRecordDataset = FixedLengthRecordDatasetV1
          TFRecordDataset = TFRecordDatasetV1
          TextLineDataset = TextLineDatasetV1
  
imports: import os
  from tensorflow.python import tf2
  from tensorflow.python.compat import v2_compat
  from tensorflow.python.data.ops import dataset_ops
  from tensorflow.python.data.ops import from_tensor_slices_op
  from tensorflow.python.data.ops import structured_function
  from tensorflow.python.data.util import convert
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import ops
  from tensorflow.python.framework import tensor_shape
  from tensorflow.python.framework import tensor_spec
  from tensorflow.python.framework import type_spec
  from tensorflow.python.ops import array_ops
  from tensorflow.python.ops import gen_dataset_ops
  from tensorflow.python.ops import gen_experimental_dataset_ops
  from tensorflow.python.types import data
  from tensorflow.python.util import nest
  from tensorflow.python.util.tf_export import tf_export
label_desc: Use image node_id 5 for calling a global function with example usage: _tf2_callback() without return types