code: def test_getsublist(self):
      eq = self.assertEqual
      CBT = browser.ChildBrowserTreeItem
  
      f1sublist = self.cbt_f1.GetSubList()
      self.assertIsInstance(f1sublist[0], CBT)
      eq(len(f1sublist), 1)
      eq(f1sublist[0].name, "f2")
  
      eq(self.cbt_F1.GetSubList(), [])
  
imports: from idlelib import browser
  from test.support import requires
  import unittest
  from unittest import mock
  from idlelib.idle_test.mock_idle import Func
  from idlelib.util import py_extensions
  from collections import deque
  import os.path
  import pyclbr
  from tkinter import Tk
  from idlelib.tree import TreeNode
label_desc: Use image node_id 7 for calling the ChildBrowserTreeItemTest obj's underlying member method code with example usage: obj.test_getsublist() without return types