code: def test_with_2d_input_array(self):
      # (H, W)
      heatmaps_arr = self.heatmaps_arr
      expected = self.expected_arr
      heatmaps = ia.HeatmapsOnImage(
          heatmaps_arr, shape=(2, 3), min_value=-2.0, max_value=10.0
      )
      assert np.allclose(heatmaps.get_arr(), heatmaps_arr)
      assert np.allclose(heatmaps.invert().get_arr(), expected)
  
imports: from __future__ import print_function, division, absolute_import
  import sys
  import numpy
  import six.moves
  import imgaug
label_desc: Use image node_id 3 for calling the TestHeatmapsOnImage_invert obj's underlying member method code with example usage: obj.test_with_2d_input_array() without return types