in php/src/Utils.php [563:577]
public static function toArray($input)
{
if (\is_array($input)) {
foreach ($input as $k => &$v) {
$v = self::toArray($v);
}
} elseif ($input instanceof Model) {
$input = $input->toMap();
foreach ($input as $k => &$v) {
$v = self::toArray($v);
}
}
return $input;
}