code: def test_combobox_creation_blank():
      w = Combobox()
      assert w.value == ""
      assert w.options == ()
      assert w.ensure_option == False
  
imports: import inspect
  import pytest
  from ipywidgets.widgets.widget_string import Combobox, Text
label_desc: Use image node_id 1 for calling a global function with example usage: test_combobox_creation_blank() without return types