code: def test_integer_counts_to_histogram(self):
      test_input = [[1, 1], [2, 2], [4, 1]]
      expected_output = pd.DataFrame(
          data={
              "c": [1, 2, 1],
              "s": [0.5, 1.5, 3.5],
              "e": [1.5, 2.5, 4.5],
          },
          columns=["c", "s", "e"],
      )
      observed_output = vcf_stats_vis._integer_counts_to_histogram(
          test_input
      )
      self.assertCountEqual(
          list(observed_output.columns),
          list(expected_output.columns),
          msg="Wrong column names",
      )
      self.assertEqual(
          list(observed_output["c"]),
          list(expected_output["c"]),
          msg="column c differs",
      )
      self.assertEqual(
          list(observed_output["s"]),
          list(expected_output["s"]),
          msg="column s differs",
      )
      self.assertEqual(
          list(observed_output["e"]),
          list(expected_output["e"]),
          msg="column e differs",
      )
      self.assertTrue((observed_output == expected_output).all().all())
  
imports: import os
  import tempfile
  from absl.testing import absltest
  import altair
  import pandas
  import tensorflow
  from deepvariant import vcf_stats_vis
label_desc: Use image node_id 3 for calling the VcfStatsVisTest obj's underlying member method code with example usage: obj.test_integer_counts_to_histogram() without return types