Django TestClient sessions - what am I missing...?

out.txt

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FAIL: test_clear_token_with_token (article.tests.test_views.ArticleViewsTest)
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Traceback (most recent call last):
  File "/root/article/tests/test_views.py", line 92, in test_clear_token_with_token
    self.assertIsNotNone(self.client.session.get('token'))
AssertionError: unexpectedly None

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test.py

    def test_clear_token_with_token(self):
        url = reverse("article:clear_token")

        # https://docs.djangoproject.com/en/1.10/topics/testing/tools/#django.test.Client.session
        # "To modify the session and then save it, it must be stored in a variable first
        # (because a new SessionStore is created every time this property is accessed):"
        session = self.client.session
        session['token'] = "loremipsum"
        session.save()

        self.assertIsNotNone(self.client.session.get('token'))