code: func (s StatusCode) IsProtocolReserved() bool {
  	switch s {
  	// [RFC6455]: {1005,1006,1015} is a reserved value and MUST NOT be set as a status code in a
  	// Close control frame by an endpoint.
  	case StatusNoStatusRcvd, StatusAbnormalClosure, StatusTLSHandshake:
  		return true
  	default:
  		return false
  	}
  }
docs: // IsProtocolReserved reports whether the code is defined by protocol specification
  // to be reserved only for application usage purpose.