old_contents: """
  Before runnning this test, start the webserver first
  """
  
  import unittest
  import requests
  
  from http import webserver
  
  class TestServer(unittest.TestCase):
      def test_root(self):
          response = requests.get('http://127.0.0.1:8888')
          self.assertEqual(response.text, """This is index file
  second line""")
      
      def test_by_file_name(self):
          response = requests.get('http://127.0.0.1:8888/index.html')
          self.assertEqual(response.text, """This is index file
  second line""")
          
      def test_with_invalid_file(self):
          response = requests.get('http://127.0.0.1:8888/indml')
          self.assertEqual(response.text, "Invalid request")
  
  if __name__ == "__main__":
      unittest.main()
new_contents: """
  Before runnning this test, start the webserver first
  """
  
  import unittest
  import requests
  
  from http import webserver
  
  class TestServer(unittest.TestCase):
      def test_root(self):
          response = requests.get('http://127.0.0.1:8888')
          self.assertEqual(response.text, """This is index file
  second line""")
      
      def test_by_file_name(self):
          response = requests.get('http://127.0.0.1:8888/index.html')
          self.assertEqual(response.text, """This is index file
  second line""")
          
      def test_with_invalid_file(self):
          response = requests.get('http://127.0.0.1:8888/indml')
          self.assertEqual(response.text, "404 Not Found")
  
  if __name__ == "__main__":
      unittest.main()
subject: fix the test_with_invalid_file() test in accordance to the modified response in response module