code: def test_treemap_base(fake_writer):
      c = TreeMap().add("演示数据", example_data)
      c.render()
      _, content = fake_writer.call_args[0]
      assert_equal(c.theme, "white")
      assert_equal(c.renderer, "canvas")
  
imports: from unittest.mock import patch
  from nose.tools import assert_equal, assert_in
  from pyecharts import options
  from pyecharts.charts import TreeMap
label_desc: Use image node_id 1 for calling a global function with example usage: test_treemap_base(fake_writer) without return types