text: from django.test import TestCase
  import datetime
  from django.utils import timezone
  from django.urls import reverse
  
  from .models import Question
  # Create your tests here.
  
  class QuestionModelTests(TestCase):
  
      def test_was_published_recently_with_future_question(self):
          # was_published_recently() returns false for the questions whose pub_date is in the future
          time = timezone.now() + datetime.timedelta(days=30)
          future_question = Question(pub_date=time)
          self.assertIs(future_question.was_published_recently(), False)
  
      def test_was_published_recently_with_old_question(self):
          """
          was_published_recently() returns False for questions whose pub_date
          is older than 1 day.
          """
          time = timezone.now() - datetime.timedelta(days=1, seconds=1)
          old_question = Question(pub_date=time)
          self.assertIs(old_question.was_published_recently(), False)
      def test_was_published_recently_with_recent_question(self):
          """
          was_published_recently() returns True for questions whose pub_date
          is within the last day.
          """
          time = timezone.now() - datetime.timedelta(hours=23, minutes=59, seconds=59)
          recent_question = Question(pub_date=time)
          self.assertIs(recent_question.was_published_recently(), True)
  
  def create_question(question_text, days):
      """
      Create a question with the given `question_text` and published the
      given number of `days` offset to now (negative for questions published
      in the past, positive for questions that have yet to be published).
      """
      time = timezone.now() + datetime.timedelta(days=days)
      return Question.objects.create(question_text=question_text, pub_date=time)
  
  
  class QuestionIndexViewTests(TestCase):
  
      def test_no_questions(self):
          """
          If no questions exist, an appropriate message is displayed.
          """
          response = self.client.get(reverse('polls:index'))
          self.assertEqual(response.status_code, 200)
          self.assertContains(response, "No polls are available.")
          self.assertQuerysetEqual(response.context['latest_question_list'], [])
      
      def test_past_question(self):
          """
          Questions with a pub_date in the past are displayed on the
          index page.
          """
          create_question(question_text="Past question.", days=-30)
          response = self.client.get(reverse('polls:index'))
          self.assertQuerysetEqual(
          response.context['latest_question_list'],
          ['<Question: Past question.>']
          )
      
      def test_future_question(self):
          """
          Questions with a pub_date in the future aren't displayed on
          the index page.
          """
          create_question(question_text="Future question.", days=30)
          response = self.client.get(reverse('polls:index'))
          self.assertContains(response, "No polls are available.")
          self.assertQuerysetEqual(response.context['latest_question_list'], [])
  
      def test_future_question_and_past_question(self):
          """
          Even if both past and future questions exist, only past questions
          are displayed.
          """
          create_question(question_text="Past question.", days=-30)
          create_question(question_text="Future question.", days=30)
          response = self.client.get(reverse('polls:index'))
          self.assertQuerysetEqual(
          response.context['latest_question_list'],
          ['<Question: Past question.>']
          )
  
      def test_two_past_questions(self):
          """
          The questions index page may display multiple questions.
          """
          create_question(question_text="Past question 1.", days=-30)
          create_question(question_text="Past question 2.", days=-5)
          response = self.client.get(reverse('polls:index'))
          self.assertQuerysetEqual(
          response.context['latest_question_list'],
          ['<Question: Past question 2.>', '<Question: Past question 1.>']
          )
  
  
  class QuestionDetailViewTests(TestCase):
      
      def test_future_question(self):
          """
          The detail view of a question with a pub_date in the future
          returns a 404 not found.
          """
          future_question = create_question(question_text='Future question.', days=5)
          url = reverse('polls:detail', args=(future_question.id,))
          response = self.client.get(url)
          self.assertEqual(response.status_code, 404)
  
      def test_past_question(self):
          """
          The detail view of a question with a pub_date in the past
          displays the question's text.
          """
          past_question = create_question(question_text='Past Question.', days=-5)
          url = reverse('polls:detail', args=(past_question.id,))
          response = self.client.get(url)
          self.assertContains(response, past_question.question_text)
  