entities.put("rarr", "\u2192");
        entities.put("darr", "\u2193");
        entities.put("harr", "\u2194");
        entities.put("crarr", "\u21b5");
        entities.put("lArr", "\u21d0");
        entities.put("uArr", "\u21d1");
        entities.put("rArr", "\u21d2");
        entities.put("dArr", "\u21d3");
        entities.put("hArr", "\u21d4");
        entities.put("forall", "\u2200");
        entities.put("part", "\u2202");

        entities.put("rarr", "\u2192");
        entities.put("darr", "\u2193");
        entities.put("harr", "\u2194");
        entities.put("crarr", "\u21b5");
        entities.put("lArr", "\u21d0");
        entities.put("uArr", "\u21d1");
        entities.put("rArr", "\u21d2");
        entities.put("dArr", "\u21d3");
        entities.put("hArr", "\u21d4");
        entities.put("forall", "\u2200");
        entities.put("part", "\u2202");

	"≩︀":                            "\u2269\ufe00",
	"⇔":                            "\u21d4",
	" ":                          "\u200a",
	"½":                            "\u00bd",
	"ℋ":                          "\u210b",
	"ъ":                          "\u044a",
	"↔":                            "\u2194",
	"⥈":                         "\u2948",

		"gtrsim;":                          '\U00002273',
		"hArr;":                            '\U000021D4',
		"hairsp;":                          '\U0000200A',
		"half;":                            '\U000000BD',
		"hamilt;":                          '\U0000210B',
		"hardcy;":                          '\U0000044A',
		"harr;":                            '\U00002194',
		"harrcir;":                         '\U00002948',

	"alefsym":  "\u2135",
	"larr":     "\u2190",
	"uarr":     "\u2191",
	"rarr":     "\u2192",
	"darr":     "\u2193",
	"harr":     "\u2194",
	"crarr":    "\u21B5",
	"lArr":     "\u21D0",
	"uArr":     "\u21D1",
	"rArr":     "\u21D2",
	"dArr":     "\u21D3",
	"hArr":     "\u21D4",
	"forall":   "\u2200",
	"part":     "\u2202",
	"exist":    "\u2203",
	"empty":    "\u2205",

	return "Bad checksum: Want " + e.Want + " does not match calculated " + e.Got
}

// IsChecksumMismatch matches if 'err' is hash.ChecksumMismatch
func IsChecksumMismatch(err error) bool {
	var herr ChecksumMismatch
	return errors.As(err, &herr)

			MuxID: m.ID,
			Op:    OpMuxServerMsg,
			Flags: c.baseFlags,
		}
		if !ok {
			hErr := handlerErr.Load()
			if debugPrint {
				fmt.Println("muxServer: Mux", m.ID, "send EOF", hErr)
			}
			msg.Flags |= FlagEOF
			if hErr != nil {
				msg.Flags |= FlagPayloadIsErr
				msg.Payload = []byte(*hErr)
			}
			msg.setZeroPayloadFlag()
			m.send(msg)
			return
		}
		msg.Payload = payload

	if hs.c.quic != nil {
		return nil
	}
	if hs.sentDummyCCS {
		return nil
	}
	hs.sentDummyCCS = true

	return hs.c.writeChangeCipherRecord()
}

// processHelloRetryRequest handles the HRR in hs.serverHello, modifies and
// resends hs.hello, and reads the new ServerHello into hs.serverHello.
func (hs *clientHandshakeStateTLS13) processHelloRetryRequest() error {
	c := hs.c

	_      = flag.Bool("ipv6", false, "")

	echConfigListB64           = flag.String("ech-config-list", "", "")
	expectECHAccepted          = flag.Bool("expect-ech-accept", false, "")
	expectHRR                  = flag.Bool("expect-hrr", false, "")
	expectedECHRetryConfigs    = flag.String("expect-ech-retry-configs", "", "")
	expectNoECHRetryConfigs    = flag.Bool("expect-no-ech-retry-configs", false, "")

			if test.expectHRR {
				if !ss.testingOnlyDidHRR {
					t.Error("server did not use HRR")
				}
				if !cs.testingOnlyDidHRR {
					t.Error("client did not use HRR")
				}
			} else {
				if ss.testingOnlyDidHRR {
					t.Error("server used HRR")
				}
				if cs.testingOnlyDidHRR {
					t.Error("client used HRR")
				}
			}
		})
	}
}