AI Blog Title Generator [closed]

Below there is part of the code for AI blog title generator in wordpress I found online. This is causing an error and I suspect this is due to the variable $jsonData which has not been initialized and is being passed as an empty string. Anyone can grab the entire html and code snippet from https://www.youtube.com/watch?v=Pl25QeHVjvM&t=417s

function jsonToModel($modelClass, $jsonData) {
try {
    return $modelClass($jsonData);
} catch (Exception $e) {
    echo "Validation error: " . $e->getMessage();
    return null;
}
}
function validateJsonWithModel($modelClass, $jsonData) {
$validatedData = [];
$validationErrors = [];

if (is_array($jsonData)) {
    foreach ($jsonData as $item) {
        try {
            $modelInstance = $modelClass($item);
            array_push($validatedData, $modelInstance);
        } catch (Exception $e) {
            array_push($validationErrors, ["error" => $e->getMessage(), "data" => $item]);
        }
    }
} elseif (is_assoc($jsonData)) {
    try {
        $modelInstance = $modelClass($jsonData);
        array_push($validatedData, $modelInstance);
    } catch (Exception $e) {
        array_push($validationErrors, ["error" => $e->getMessage(), "data" => $jsonData]);
    }
} else {
    throw new ValueError("Invalid JSON data type. Expected associative array or array.");
}
return [$validatedData, $validationErrors];

}