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<?php $sort_dates = function($a, $b) { $a = strtotime($a['birthday']); $b = strtotime($b['birthday']); if ($a == $b) { return 0; } return ($a < $b) ? -1 : 1; }; usort($upcoming, $sort_dates);

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34.86 ms | 402 KiB | 5 Q