Call to undefined function kod_tamamla() hatası

for($j=1;$j<$kacmac;$j++){
$codeal=explode('<div class="BetCode">',$ikincifor[$j]);
$coder=explode('<span>',$codeal[1]);
$code=kod_tamamla(substr($coder[1],0,3));//MA� KODU
$saatal=explode('<div class="BetHour">',$ikincifor[$j]);
$clocker=explode('<span>',$saatal[1]);
$saat=substr($clocker[1],0,5);//SAAT
$sayir=explode(':',$saat);