How to use the creoleparser.core.bldr.tag function in Creoleparser

def _activitylink(offering, macro, environ, *act_name):
    act = _find_activity(offering, macro['arg_string'])
    attrs = {}
    if isinstance(act, Activity):
        text = act.name
        attrs['href'] = act.get_absolute_url()
    else:
        # error
        text = act
        attrs['class'] = 'empty'

    return creoleparser.core.bldr.tag.__getattr__('a')(text, **attrs)

def _activitylink(offering, macro, environ, *act_name):
    act = _find_activity(offering, macro['arg_string'])
    attrs = {}
    if isinstance(act, Activity):
        text = act.name
        attrs['href'] = act.get_absolute_url()
    else:
        # error
        text = act
        attrs['class'] = 'empty'

    return creoleparser.core.bldr.tag.__getattr__('a')(text, **attrs)

def _build(self, mo, element_store, environ):
        lang = mo.group(1)
        code = mo.group(2).rstrip()

        return creoleparser.core.bldr.tag.__getattr__(self.tag)(
            creoleparser.core.fragmentize(code, self.child_elements,
                                          element_store, environ, remove_escapes=False),
            class_="highlight lang-" + lang,
            lang=lang # the most restrictive markup rendering strips the class attribute, but not lang.
        )

# all pages [with the given prefix] for this offering
    if prefix:
        pages = Page.objects.filter(offering=offering, label__startswith=prefix)
    else:
        pages = Page.objects.filter(offering=offering)

    # ... except this page (if known)
    if pageversion:
        pages = pages.exclude(id=pageversion.page_id)

    elements = []
    for p in pages:
        link = creoleparser.core.bldr.tag.__getattr__('a')(p.current_version().title or p.label, href=p.label)
        li = creoleparser.core.bldr.tag.__getattr__('li')(link)
        elements.append(li)
    return creoleparser.core.bldr.tag.__getattr__('ul')(elements, **{'class': 'filelist'})