For the county where DeSantis Ron is from, what is the average female median age?
average female median age refers to Divide (Sum(female_median_age), Count(county))
SELECT SUM(T4.female_median_age) / COUNT(T1.county) FROM country 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 INNER JOIN zip_data AS T4 ON T1.zip_code = T4.zip_code WHERE T3.first_name = 'DeSantis' AND T3.last_name = 'Ron'