private static function _roundDownFractionalSeconds(\DateTimeImmutable $dt): \DateTimeImmutable
    {
        return \DateTimeImmutable::createFromFormat("Y-m-d H:i:s",
            $dt->format("Y-m-d H:i:s"), $dt->getTimezone());
    }
private static function _roundDownFractionalSeconds(\DateTimeImmutable $dt): \DateTimeImmutable
    {
        return \DateTimeImmutable::createFromFormat("Y-m-d H:i:s",
            $dt->format("Y-m-d H:i:s"), $dt->getTimezone());
    }
private static function _roundDownFractionalSeconds ( \ DateTimeImmutable $ dt ) : \ DateTimeImmutable { return \ DateTimeImmutable :: createFromFormat ( "Y-m-d H:i:s" , $ dt -> format ( "Y-m-d H:i:s" ) , $ dt -> getTimezone ( ) ) ; }
Rounds a \DateTimeImmutable value such that fractional
seconds are removed.

@param \DateTimeImmutable $dt
@return \DateTimeImmutable
Rounds a \ DateTimeImmutable value such that fractional seconds are removed .