who are the senators of kansas 2013?
(JOIN (R government.government_position_held.office_holder) (AND (JOIN government.government_position_held.time_macro 2013^^http://www.w3.org/2001/XMLSchema#date) (AND (JOIN government.government_position_held.basic_title m.048zv9l) (JOIN (R government.political_district.representatives) m.0488g))))