code: def test_widget_enabler_context_manager():
      alt.data_transformers.enable("json")
      alt.renderers.enable("mimetype")
  
      assert alt.data_transformers.active == "json"
      assert alt.renderers.active == "mimetype"
  
      with vf.enable_widget():
          assert alt.data_transformers.active == "vegafusion-feather"
          assert alt.renderers.active == "vegafusion-widget"
  
      assert alt.data_transformers.active == "json"
      assert alt.renderers.active == "mimetype"
  
      ctx = vf.enable_widget()
      assert alt.data_transformers.active == "vegafusion-feather"
      assert alt.renderers.active == "vegafusion-widget"
      assert repr(ctx) == "vegafusion.enable_widget()"
  
imports: import altair
  import vegafusion
label_desc: Use image node_id 1 for calling a global function with example usage: test_widget_enabler_context_manager() without return types