$listing = PetListing::$objects->get($petListingId);
    } catch (DoesNotExist $e) {
        $listing = new PetListing();
    }
} else {
    $listing = new PetListing();
}
if ($listing->id) {
    $pageTitle = "Edit Pet Listing";
    $user = $listing->getUser();
} else {
    $pageTitle = "Add Pet Listing";
    $user = new RegisteredUser();
}
if ($listing->approved && $listing->approvedById) {
    $approvedByUser = $listing->getApprovedByUser();
} else {
    $approvedByUser = new RegisteredUser();
}
/**
 * Generate and echo a set of radio buttons with the given name, values, labels, 
 * and selected value.
 */
function makeRadioButtons($name, $values, $labels, $selectedValue)
{
    for ($i = 0; $i < count($values); $i++) {
        $value = $values[$i];
        $label = $labels[$i];
        $checked = $value == $selectedValue ? 'checked="checked"' : ' ';
        echo "\n            <label class='radio-inline'>\n                <input type='radio' name='{$name}' value='{$value}' {$checked} />\n                {$label}\n            </label>";
    }