Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE district (city_population INTEGER, city_area VARCHAR)
### Question:
Find the total population of the top 3 districts with the largest area.
### Answer:
SELECT SUM(city_population) FROM district ORDER BY city_area DESC LIMIT 3