How to use the djet.assertions.StatusCodeAssertionsMixin function in djet

def test_post_should_not_login_if_empty_request(self):
        data = {}
        request = self.factory.post(data=data)

        response = self.view(request)

        self.assert_status_equal(response, status.HTTP_400_BAD_REQUEST)
        self.assertEqual(
            response.data['non_field_errors'],
            [djoser.constants.INVALID_CREDENTIALS_ERROR]
        )


class LogoutViewTest(restframework.APIViewTestCase,
                     assertions.StatusCodeAssertionsMixin):
    view_class = djoser.views.LogoutView

    def setUp(self):
        self.signal_sent = False

    def signal_receiver(self, *args, **kwargs):
        self.signal_sent = True

    def test_post_should_logout_logged_in_user(self):
        user = create_user()
        user_logged_out.connect(self.signal_receiver)
        request = self.factory.post(user=user)

        response = self.view(request)

        self.assert_status_equal(response, status.HTTP_204_NO_CONTENT)

'username': 'john',
            'email': 'john@beatles.com',
            'password': 'secret',
        }

        request = self.factory.post(data=data)
        response = self.view(request)

        self.assert_status_equal(response, status.HTTP_400_BAD_REQUEST)
        self.assertEqual(
            response.data, [djoser.constants.CANNOT_CREATE_USER_ERROR]
        )


class LoginViewTest(restframework.APIViewTestCase,
                    assertions.StatusCodeAssertionsMixin,
                    assertions.InstanceAssertionsMixin):
    view_class = djoser.views.LoginView

    def setUp(self):
        self.signal_sent = False

    def signal_receiver(self, *args, **kwargs):
        self.signal_sent = True

    def test_post_should_login_user(self):
        user = create_user()
        data = {
            'username': user.username,
            'password': user.raw_password,
        }
        user_logged_in.connect(self.signal_receiver)

data = {
            'new_password': 'new password',
            'current_password': 'secret',
        }
        request = self.factory.post(user=user, data=data)
        djoser.utils.login_user(request, user)

        response = self.view(request)

        self.assert_status_equal(response, status.HTTP_204_NO_CONTENT)
        is_logged = authtoken.models.Token.objects.filter(user=user).exists()
        self.assertTrue(is_logged)


class SetUsernameViewTest(restframework.APIViewTestCase,
                          assertions.StatusCodeAssertionsMixin):
    view_class = djoser.views.SetUsernameView

    def test_post_should_set_new_username(self):
        user = create_user()
        data = {
            'new_username': 'ringo',
            'current_password': 'secret',
        }
        request = self.factory.post(user=user, data=data)

        response = self.view(request)

        self.assert_status_equal(response, status.HTTP_204_NO_CONTENT)
        user = utils.refresh(user)
        self.assertEqual(data['new_username'], user.username)

self.assert_status_equal(response, status.HTTP_400_BAD_REQUEST)
        self.assertEqual(response.data['non_field_errors'], [djoser.constants.INVALID_CREDENTIALS_ERROR])
        self.assertTrue(self.signal_sent)

    def test_post_should_not_login_if_empty_request(self):
        data = {}
        request = self.factory.post(data=data)

        response = self.view(request)

        self.assert_status_equal(response, status.HTTP_400_BAD_REQUEST)
        self.assertEqual(response.data['non_field_errors'], [djoser.constants.INVALID_CREDENTIALS_ERROR])


class LogoutViewTest(restframework.APIViewTestCase,
                     assertions.StatusCodeAssertionsMixin):
    view_class = djoser.views.LogoutView

    def setUp(self):
        self.signal_sent = False

    def signal_receiver(self, *args, **kwargs):
        self.signal_sent = True

    def test_post_should_logout_logged_in_user(self):
        user = create_user()
        user_logged_out.connect(self.signal_receiver)
        request = self.factory.post(user=user)

        response = self.view(request)

        self.assert_status_equal(response, status.HTTP_204_NO_CONTENT)

response = self.view(request)

        self.assert_status_equal(response, status.HTTP_401_UNAUTHORIZED)

    def test_options(self):
        user = create_user()
        request = self.factory.options(user=user)

        response = self.view(request)

        self.assert_status_equal(response, status.HTTP_200_OK)


class PasswordResetViewTest(restframework.APIViewTestCase,
                            assertions.StatusCodeAssertionsMixin,
                            assertions.EmailAssertionsMixin):
    view_class = djoser.views.PasswordResetView

    def test_post_should_send_email_to_user_with_password_rest_link(self):
        user = create_user()
        data = {
            'email': user.email,
        }
        request = self.factory.post(data=data)

        response = self.view(request)

        self.assert_status_equal(response, status.HTTP_204_NO_CONTENT)
        self.assert_emails_in_mailbox(1)
        self.assert_email_exists(to=[user.email])
        site = djoser.utils.get_current_site(request)

**{'PASSWORD_RESET_SHOW_EMAIL_NOT_FOUND': True}))
    def test_post_should_return_bad_request_if_user_does_not_exist(self):
        data = {
            'email': 'john@beatles.com',
        }
        request = self.factory.post(data=data)

        response = self.view(request)

        self.assert_status_equal(response, status.HTTP_400_BAD_REQUEST)
        self.assertEqual(response.data['email'][0],
                         djoser.constants.EMAIL_NOT_FOUND)


class PasswordResetConfirmViewTest(restframework.APIViewTestCase,
                                   assertions.StatusCodeAssertionsMixin):
    view_class = djoser.views.PasswordResetConfirmView

    def test_post_should_set_new_password(self):
        user = create_user()
        data = {
            'uid': djoser.utils.encode_uid(user.pk),
            'token': default_token_generator.make_token(user),
            'new_password': 'new password',
        }

        request = self.factory.post(data=data)

        response = self.view(request)

        self.assert_status_equal(response, status.HTTP_204_NO_CONTENT)
        user = utils.refresh(user)

assertions.StatusCodeAssertionsMixin):
    view_class = djoser.views.RootView

    def test_get_should_return_urls_mapping(self):
        request = self.factory.get()
        view_object = self.create_view_object(request)

        response = view_object.dispatch(request)

        self.assert_status_equal(response, status.HTTP_200_OK)
        for key in view_object.get_urls_mapping().keys():
            self.assertIn(key, response.data)


class RegistrationViewTest(restframework.APIViewTestCase,
                           assertions.StatusCodeAssertionsMixin,
                           assertions.EmailAssertionsMixin,
                           assertions.InstanceAssertionsMixin):
    view_class = djoser.views.RegistrationView

    def test_post_should_create_user_without_login(self):
        data = {
            'username': 'john',
            'password': 'secret',
            'csrftoken': 'asdf',
        }
        request = self.factory.post(data=data)

        response = self.view(request)

        self.assert_status_equal(response, status.HTTP_201_CREATED)
        self.assertTrue('password' not in response.data)

**{'PASSWORD_RESET_SHOW_EMAIL_NOT_FOUND': True}))
    def test_post_should_return_bad_request_if_user_does_not_exist(self):
        data = {
            'email': 'john@beatles.com',
        }
        request = self.factory.post(data=data)

        response = self.view(request)

        self.assert_status_equal(response, status.HTTP_400_BAD_REQUEST)
        self.assertEqual(response.data['email'][0],
                         djoser.constants.EMAIL_NOT_FOUND)


class PasswordResetConfirmViewTest(restframework.APIViewTestCase,
                                   assertions.StatusCodeAssertionsMixin):
    view_class = djoser.views.PasswordResetConfirmView

    def test_post_should_set_new_password(self):
        user = create_user()
        data = {
            'uid': djoser.utils.encode_uid(user.pk),
            'token': default_token_generator.make_token(user),
            'new_password': 'new password',
        }

        request = self.factory.post(data=data)

        response = self.view(request)

        self.assert_status_equal(response, status.HTTP_204_NO_CONTENT)
        user = utils.refresh(user)

For example::

        >>> with self.assert_instance_deleted(Article, slug='lorem-ipsum'):
        ...     Article.objects.get(slug='lorem-ipsum').delete()
        """
        return _InstanceContext(
            self.assert_instance_exists,
            self.assert_instance_does_not_exist,
            model_class,
            **kwargs
        )


class CompleteAssertionsMixin(
    StatusCodeAssertionsMixin,
    EmailAssertionsMixin,
    MessagesAssertionsMixin,
    InstanceAssertionsMixin,
):
    pass