code: def test_layout(self):
      style = self.style
      self.assertRaises(tkinter.TclError, style.layout, "NotALayout")
      tv_style = style.layout("Treeview")
  
      # "erase" Treeview layout
      style.layout("Treeview", "")
      self.assertEqual(
          style.layout("Treeview"), [("null", {"sticky": "nswe"})]
      )
  
      # restore layout
      style.layout("Treeview", tv_style)
      self.assertEqual(style.layout("Treeview"), tv_style)
  
      # should return a list
      self.assertIsInstance(style.layout("TButton"), list)
  
      # correct layout, but "option" doesn't exist as option
      self.assertRaises(
          tkinter.TclError,
          style.layout,
          "Treeview",
          [("name", {"option": "inexistent"})],
      )
  
file_path: catboost/contrib/tools/python/src/Lib/lib-tk/test/test_ttk/test_style.py
imports: import unittest
  import Tkinter
  import ttk
  from test.test_support import requires, run_unittest
  from test_ttk.support import AbstractTkTest
label_desc: Use image node_id 5 for calling the StyleTest obj's underlying member method code with example usage: obj.test_layout() without return types