code: def test_heatmap_matplotlib(compute_backend_df):
      w = dd.data_heatmap(compute_backend_df)
      assert isinstance(w, HeatmapWidget), "Not a Heatmap Widget"
      assert isinstance(w.show(), matplotlib.figure.Figure)
  
file_path: data-describe/tests/test_data_heatmap.py
imports: import matplotlib
  import pytest
  import plotly
  import data_describe
  from data_describe.core.heatmap import HeatmapWidget
label_desc: Use image node_id 1 for calling a global function with example usage: test_heatmap_matplotlib(compute_backend_df) without return types