def METHOD_NAME(self):
    h = Headers({"Content-Type": "text/html", "Content-Length": 1234})
    assert h["Content-Type"]
    assert h["Content-Length"]
    self.assertRaises(KeyError, h.__getitem__, "Accept")
    self.assertEqual(h.get("Accept"), None)
    self.assertEqual(h.getlist("Accept"), [])
    self.assertEqual(h.get("Accept", "*/*"), b"*/*")
    self.assertEqual(h.getlist("Accept", "*/*"), [b"*/*"])
    self.assertEqual(
        h.getlist("Accept", ["text/html", "images/jpeg"]),
        [b"text/html", b"images/jpeg"],
    )