code: def _unwrap_acc(a: WrappedAggType) -> Tuple[AggType, bool]:
      """
      Unwrap the accumulation, which we assume has been wrapped (via _wrap_acc) with a
      numeric boolean flag indicating whether or not this accumulation contains real data.
  
      Args:
          a: The wrapped accumulation value that we wish to unwrap.
  
      Returns:
          A tuple containing the unwrapped accumulation value and a boolean indicating
          whether the accumulation contains real data.
      """
      has_data = a[-1] == 1
      a = a[:-1]
      if len(a) == 1:
          a = a[0]
      return a, has_data
  
file_path: ray/python/ray/data/_internal/null_aggregate.py
imports: from types import ModuleType
  from typing import Any, Callable, Tuple, Union
  import numpy
  from ray.data.block import AggType, Block, KeyType, T, U
label_desc: Use image node_id 2 for calling a global function with example usage: _unwrap_acc(a) and returns: a,  has_data