          """Ensure POSTing with expired access token fails with an 'Invalid token' error"""
          self.access_token.expires = datetime.datetime.now() - datetime.timedelta(seconds=10)  # 10 seconds late
          self.access_token.save()
          auth = self._create_authorization_header()
          params = self._client_credentials_params()
          response = self.csrf_client.post('/oauth2-test/', params, HTTP_AUTHORIZATION=auth)
          self.assertIn(response.status_code, (status.HTTP_401_UNAUTHORIZED, status.HTTP_403_FORBIDDEN))
          self.assertIn('Invalid token', response.content)
  
      @unittest.skipUnless(oauth2_provider, 'django-oauth2-provider not installed')
      def test_post_form_with_invalid_scope_failing_auth(self):
 
</s> remove         params = self._client_credentials_params()
        response = self.csrf_client.post('/oauth2-test/', params, HTTP_AUTHORIZATION=auth)
 </s> add         response = self.csrf_client.post('/oauth2-test/', HTTP_AUTHORIZATION=auth) </s> remove         response = self.csrf_client.post('/oauth2-with-scope-test/', params, HTTP_AUTHORIZATION=auth)
 </s> add         response = self.csrf_client.post('/oauth2-with-scope-test/', HTTP_AUTHORIZATION=auth) </s> remove         params = self._client_credentials_params()
        response = self.csrf_client.get('/oauth2-with-scope-test/', params, HTTP_AUTHORIZATION=auth)
 </s> add         response = self.csrf_client.get('/oauth2-with-scope-test/', HTTP_AUTHORIZATION=auth) </s> remove         params = self._client_credentials_params()
        response = self.csrf_client.post('/oauth2-with-scope-test/', params, HTTP_AUTHORIZATION=auth)
 </s> add         response = self.csrf_client.post('/oauth2-with-scope-test/', HTTP_AUTHORIZATION=auth)
        response = self.csrf_client.post('/oauth2-test/', HTTP_AUTHORIZATION=auth)
          """Ensure POSTing with expired access token fails with an 'Invalid token' error"""
          self.access_token.expires = datetime.datetime.now() - datetime.timedelta(seconds=10)  # 10 seconds late
          self.access_token.save()
          auth = self._create_authorization_header()
        response = self.csrf_client.post('/oauth2-test/', HTTP_AUTHORIZATION=auth)
        response = self.csrf_client.post('/oauth2-test/', HTTP_AUTHORIZATION=auth)
          self.assertIn(response.status_code, (status.HTTP_401_UNAUTHORIZED, status.HTTP_403_FORBIDDEN))
          self.assertIn('Invalid token', response.content)
  
      @unittest.skipUnless(oauth2_provider, 'django-oauth2-provider not installed')
      def test_post_form_with_invalid_scope_failing_auth(self):
keep keep keep keep replace replace keep keep keep keep keep
 Remove client credentials from all OAuth 2 tests 
rest_framework/tests/authentication.py