code: def test_geo_lines(fake_writer):
      c = (
          Geo()
          .add_schema(maptype="china")
          .add(
              "",
              [("广州", 55), ("北京", 66), ("杭州", 77), ("重庆", 88)],
              type_=ChartType.EFFECT_SCATTER,
              color="white",
          )
          .add(
              "geo",
              [("广州", "上海"), ("广州", "北京"), ("广州", "杭州"), ("广州", "重庆")],
              type_=ChartType.LINES,
              effect_opts=opts.EffectOpts(
                  symbol=SymbolType.ARROW, symbol_size=6, color="blue"
              ),
              linestyle_opts=opts.LineStyleOpts(curve=0.2),
          )
          .set_series_opts(label_opts=opts.LabelOpts(is_show=False))
          .set_global_opts(title_opts=opts.TitleOpts(title="Geo-Lines"))
      )
      assert_equal(c.theme, "white")
      c.render()
      _, content = fake_writer.call_args[0]
      assert_in("canvas", content)
  
imports: from unittest.mock import patch
  from nose.tools import assert_equal, assert_in
  from pyecharts import options
  from pyecharts.charts import Geo
  from pyecharts.faker import Faker
  from pyecharts.globals import ChartType, SymbolType
label_desc: Use image node_id 6 for calling a global function with example usage: test_geo_lines(fake_writer) without return types