code: def test_global_theme_overriding():
      gg.LetsPlot.set_theme(theme(legend_position="bottom"))
  
      spec = gg.ggplot() + _geom("foo") + theme(legend_position="top")
  
      assert "top" == spec.as_dict()["theme"]["legend_position"]
  
imports: import lets_plot
  from lets_plot import element_blank
  from lets_plot import element_rect
  from lets_plot.plot import theme
  from lets_plot.plot.geom import _geom
  from lets_plot.plot.theme_set import theme_classic, flavor_darcula, flavor_solarized_dark
label_desc: Use image node_id 11 for calling a global function with example usage: test_global_theme_overriding() without return types