public function withSerialNumber($serial): self
    {
        $obj = clone $this;
        $obj->_serialNumber = strval($serial);
        return $obj;
    }
public function withSerialNumber($serial): self
    {
        $obj = clone $this;
        $obj->_serialNumber = strval($serial);
        return $obj;
    }
public function withSerialNumber ( $ serial ) : self { $ obj = clone $ this ; $ obj -> _serialNumber = strval ( $ serial ) ; return $ obj ; }
Get self with serial number.

@param int|string $serial
@return self
Get self with serial number .