old_contents: from django.test import TestCase
  from teams.models import Team,TeamManager,WaitList
  from users.models import User,UserManager
  
  class TestWaitList(TestCase):
      def setUp(self):
          pass
  
  
new_contents: from django.test import TestCase
  from teams.models import Team,TeamManager,WaitList
  from users.models import User,UserManager
  from django.core.exceptions import ObjectDoesNotExist
  
  class TestWaitList(TestCase):
      def setUp(self):
          self.user_email = "test@example.com"
          self.user_password = "12345678"
          self.user = User()
  
          self.non_exist_user_email = "no@example.com"
  
          self.team_name = "Team1"
          self.team = Team()
  
          self.non_exist_team_name = "NoTeam"
  
          User.objects.create_user(
              email = self.user_email,
              password = self.user_password
          )
  
          Team.objects.create_team(
              name = self.team_name
          )
  
      def test_user_and_team_should_be_put_wait_list_using_manager(self):
          try:
              WaitList.objects.append_list(
                  team_name=self.team_name,
                  user_email=self.user_email
              )
          except:
              self.fail("Append to wait list should be success.")
  
      def test_append_wait_list_should_not_be_working_with_invalid_argument(self):
          self.assertRaises(
              ObjectDoesNotExist,WaitList.objects.append_list,
              team_name = self.team_name,
              user_email = self.non_exist_user_email
          )
  
      def test_appended_wait_list_should_be_get_using_manager_with_team_argument(self):
          self.assertRaises(
              ObjectDoesNotExist, WaitList.objects.get_wait_list,
              team_name = self.non_exist_team_name
          )
  
subject: add test code for Wait List