new_contents: from django.test import TestCase
  from teams.models import Team, WaitList
  from users.models import User
  from django.utils import timezone
  from django.core.exceptions import ValidationError
  
  class WaitList_wait_member_to_team_test(TestCase):
      def setUp(self):
          self.user_email = "test@example.com"
          self.user_password = "12345678"
          self.user_email_2 = "test2@example.com"
  
          self.team_name = "Team1"
          self.team_name_2 = "Team2"
  
          self.user = User.objects.create_user(
              email = self.user_email,
              password = self.user_password
          )
  
          self.team = Team.objects.create_team(
              name = self.team_name
          )
  
          self.user_2 = User.objects.create_user(
              email = self.user_email_2,
              password = self.user_password
          )
  
          self.team_2 = Team.objects.create_team(
              name = self.team_name_2
          )
  
          self.wait_list = WaitList.objects.create_wait_list(
              self.team,
              self.user,
          )
          
      def test_wait_member_could_get_all_belonged_team(self):
          try:
              self.user.wait_member.all()
          except:
              self.fail("getting all team belonged failed")
     
      def test_wait_member_could_cancel_to_request_to_join_team(self):
          try:
              self.user.wait_list_wait_member.cancel_to_request_to_team(self.team)
          except ValidationError:
              self.fail("cancel to request to team has occured an error")
  
subject: test wait_list_wait_member_to_team