code: def is_cross_slice_key(
      slice_key: Union[SliceKeyType, CrossSliceKeyType]
  ) -> bool:
      """Returns whether slice_key is cross_slice or not."""
      return get_slice_key_type(slice_key) == CrossSliceKeyType
  
imports: import itertools
  from typing import Any, Callable, Dict, Generator, Iterable, List, NamedTuple, Optional, Tuple, Union
  import apache_beam
  import numpy
  import tensorflow
  from tensorflow_model_analysis import constants
  from tensorflow_model_analysis.api import types
  from tensorflow_model_analysis.proto import config_pb2
  from tensorflow_model_analysis.proto import metrics_for_slice_pb2
  from tensorflow_model_analysis.slicer import slice_accessor
label_desc: Use image node_id 12 for calling a global function with example usage: is_cross_slice_key(slice_key) and returns: unknown