public function form_open($action = null) {
if (is_null($action)) {
$action = MasterPress::$action;
}
?>
<form autocomplete="off" action="<?php echo MPV::form_action(array(), true, $action) ?>" method="post" class="mpv-<?php echo $this->key() ?>-form mpv-<?php echo $this->key() ?>-<?php echo MPC::action_type() ?>">
<?php
wp_nonce_field( $action );
MPV::id_form_field();
MPV::parent_form_field();
MPV::gparent_form_field();
MPV::postback_form_field();
MPV::return_form_field();
MPV::redirect_form_field();
}