Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE district ( city_population INTEGER, city_area VARCHAR )

### Question ###
Find the total population of the top 3 districts with the largest area.

### Accurate SQL ###

SELECT SUM(city_population) FROM district ORDER BY city_area DESC LIMIT 3