Global function in file auto_prepend.php:

/**
 * Return a text in the selected language
 * Replaces variables of the form {var} with value from argument $values
 * @param $label Label of text to return
 * @param $values Associative array containing values to fill in (no quoting)
 * @param $language Optional language to return text in.
 * @return Localized text string with variables replaced by their values
 */
function ET($label, $values = null, $language = null)
{
    it_text::init();
    return $GLOBALS['it_text']->etext($label, $values, $language);
}