def METHOD_NAME(self, fossils):
    results = fossils['results']
    if not isinstance(results, list):
        results = [results]
    cal = ical.Calendar()
    cal.add('version', '2.0')
    cal.add('prodid', '-//CERN//INDICO//EN')
    now = now_utc()
    for fossil in results:
        if '_fossil' in fossil:
            mapper = ICalSerializer._mappers.get(fossil['_fossil'])
        else:
            mapper = self._extra_args.get('ical_serializer')
        if mapper:
            mapper(cal, fossil, now)
    return cal.to_ical()