person_filter = Filter(Person.fields, person_filter)
sql += " AND (%s) %s" % person_filter.sql(api, "AND")
elif isinstance (person_filter, StringTypes):
person_filter = Filter(Person.fields, person_filter)
sql += " AND (%s) %s" % person_filter.sql(api, "AND")
elif isinstance (person_filter, StringTypes):