[Zope] attribute error: absolute_url ... answer to my own question ;-)

hi it works as follows: <dtml-if "_.has_key ('text_css_styles')"><link rel=stylesheet type="text/css" href="<dtml-var "text_css_styles.absolute_url ()">"></dtml-if> thx, though I was fast enough to get it myself but if someone can tell me WHY this works, your answer is appreciated! Wolfgang