'Map items corresponding to URL and CDN attributes to an ast expression.'

def _wrap_build_attributes(self, el, items, options):

    if options.get('rendering_bundle'):
        return items
    url_att = self.URL_ATTRS.get(el.tag)
    cdn_att = self.CDN_TRIGGERS.get(el.tag)
    def process(item):
        if (isinstance(item, tuple) and (item[0] in (url_att, cdn_att))):
            return (item[0], ast.Call(func=ast.Attribute(value=ast.Name(id='self', ctx=ast.Load()), attr='_website_build_attribute', ctx=ast.Load()), args=[ast.Str(el.tag), ast.Str(item[0]), item[1], ast.Name(id='options', ctx=ast.Load()), ast.Name(id='values', ctx=ast.Load())], keywords=[], starargs=None, kwargs=None))
        else:
            return item
    return map(process, items)
