new_contents: from django.test import TestCase
  from django.contrib.auth.models import User
  
  from participants.models import Participant, ParticipantTeam
  
  
  class BaseTestCase(TestCase):
  
      def setUp(self):
          self.user = User.objects.create(
              username='user',
              email='user@test.com',
              password='password'
              )
          self.participant_team = ParticipantTeam.objects.create(
              team_name='Participant Team',
              created_by=self.user)
  
  
  class ParticipantTestCase(BaseTestCase):
  
      def setUp(self):
          super(ParticipantTestCase, self).setUp()
          self.participant = Participant.objects.create(
              user=self.user,
              status=Participant.ACCEPTED,
              team=self.participant_team
          )
  
      def test__str__(self):
          self.assertEqual('{}'.format(self.participant.user),
                           self.participant.__str__())
  
  
  class ParticipantTeamTestCase(BaseTestCase):
  
      def setUp(self):
          super(ParticipantTeamTestCase, self).setUp()
  
      def test__str__(self):
          self.assertEqual(self.participant_team.team_name,
                           self.participant_team.__str__())
  
subject: Add tests for __unicode__ functions in model. (#1017)