PHP: Converting Numbers functions Persian To English & English To Persian

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function convertNumbersFaToEn($number)
{
    $persian = array('۰', '۱', '۲', '۳', '۴', '۵', '۶', '۷', '۸', '۹');
    $num = range(0, 9);
    return str_replace($persian, $num, $number);
}
function convertNumbersEnToFA($number)
{
    $persian = array('۰', '۱', '۲', '۳', '۴', '۵', '۶', '۷', '۸', '۹');
    $num = range(0, 9);
    return  str_replace( $num,$persian ,$number);
}