Indicate the name of the congressman represent in Guanica.
name of congressman implies full name which refers to first_name, last_name; Guanica is the city;
SELECT T3.first_name, T3.last_name FROM zip_data AS T1 INNER JOIN zip_congress AS T2 ON T1.zip_code = T2.zip_code INNER JOIN congress AS T3 ON T2.district = T3.cognress_rep_id WHERE T1.city = 'Guanica'