<?
   interface IDateTimeProvider
    {
        public function date($format);
        public function time();
    }

    class DateTimeProvider implements IDateTimeProvider
    {
        public function date($format)
        {
            return date($format);
        }
        public function time()
        {
            return time();
        }
    }

$dtp = new DateTimeProvider();
echo $dtp->time();

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