code: def estimate_heatmaps_norm_type(heatmaps):
      type_str = estimate_normalization_type(heatmaps)
      valid_type_strs = [
          "None",
          "array[float]",
          "HeatmapsOnImage",
          "iterable[empty]",
          "iterable-array[float]",
          "iterable-HeatmapsOnImage",
      ]
      _assert_is_of_norm_type(type_str, valid_type_strs, "heatmaps")
      return type_str
  
imports: from __future__ import print_function, division, absolute_import
  import functools
  import numpy
  from ..None import imgaug
  from ..None import dtypes
  from .base import IAugmentable
label_desc: Use image node_id 24 for calling a global function with example usage: estimate_heatmaps_norm_type(heatmaps) and returns: type_str