code: func (s StatusCode) IsProtocolDefined() bool {
  	switch s {
  	case StatusNormalClosure,
  		StatusGoingAway,
  		StatusProtocolError,
  		StatusUnsupportedData,
  		StatusInvalidFramePayloadData,
  		StatusPolicyViolation,
  		StatusMessageTooBig,
  		StatusMandatoryExt,
  		StatusInternalServerError,
  		StatusNoStatusRcvd,
  		StatusAbnormalClosure,
  		StatusTLSHandshake:
  		return true
  	}
  	return false
  }
docs: // IsProtocolDefined reports whether the code is already defined by protocol specification.