'Helper method to render one option
@param item: the item as tuple (key, label, value, tooltip),
value=True indicates that the item is selected'

@staticmethod
def _render_item(item):

    (key, label, value, tooltip) = item
    attr = {'_value': key}
    if value:
        attr['_selected'] = 'selected'
    if tooltip:
        attr['_title'] = tooltip
    return OPTION(label, **attr)
