code: def test_multiple_lines(self):  # insert and delete
      self.text.insert("1.0", "hello")
  
      self.text.insert("1.3", "1\n2\n3\n4\n5")
      self.assertEqual(
          self.text.get("1.0", "end"), "hel1\n2\n3\n4\n5lo\n"
      )
  
      self.text.delete("1.3", "5.1")
      self.assertEqual(self.text.get("1.0", "end"), "hello\n")
  
imports: import unittest
  from test.test_support import requires
  from _tkinter import TclError
label_desc: Use image node_id 10 for calling the TextTest obj's underlying member method code with example usage: obj.test_multiple_lines() without return types