code: def test_heatmap_data():
      data = HeatMap(np.array([[3, 4, 1], [5, 6, 1], [7, 8, 0.5]])).data
      assert isinstance(data, list)
      assert len(data) == 3
      for i in range(len(data)):
          assert isinstance(data[i], list)
          assert len(data[i]) == 3
  
file_path: folium/tests/plugins/test_heat_map.py
imports: import numpy
  import pytest
  from jinja2 import Template
  import folium
  from folium.plugins import HeatMap
  from folium.utilities import normalize
label_desc: Use image node_id 2 for calling a global function with example usage: test_heatmap_data() without return types