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def test_img_cdn_too_small(self):

    self.rv = self.client.get(self.url('/image/png'), environ_base=env(), headers=headers())
    self.assertEqual('image/png', self.rv.content_type, msg=self.dump())
    self.assertIn('\x89PNG', self.rv.data, msg=self.dump())
    self.assertEqual(8090, len(self.rv.data), msg=self.dump())
    with self.app.test_client() as c:
        self.rv2 = c.get(self.url('/image/png'), environ_base=env(), headers=headers())
        self.assertEqual(200, self.rv2.status_code, msg=self.dump())
        self.assertEqual('image/png', self.rv2.content_type, msg=self.dump())
        self.assertEqual(self.rv.data, self.rv2.data, msg=self.dump())
