If the passengers are 15,505,566, what is the iata code?
CREATE TABLE table_18047346_4 (
    iata_code VARCHAR,
    passengers VARCHAR
)
SELECT iata_code FROM table_18047346_4 WHERE passengers = "15,505,566"
Below are sql tables schemas paired with instruction that describes a task. Using valid SQLite, write a response that appropriately completes the request for the provided tables. ### Instruction: If the passengers are 15,505,566, what is the iata code? ### Input: CREATE TABLE table_18047346_4 (
    iata_code VARCHAR,
    passengers VARCHAR
) ### Response: SELECT iata_code FROM table_18047346_4 WHERE passengers = "15,505,566"