What is the quantity preserved for the serial number of mallet and simple articulated locomotives?
CREATE TABLE table_name_19 (
    quantity_preserved VARCHAR,
    serial_numbers VARCHAR
)
SELECT quantity_preserved FROM table_name_19 WHERE serial_numbers = "mallet and simple articulated locomotives"
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: What is the quantity preserved for the serial number of mallet and simple articulated locomotives? ### Input: CREATE TABLE table_name_19 (
    quantity_preserved VARCHAR,
    serial_numbers VARCHAR
) ### Response: SELECT quantity_preserved FROM table_name_19 WHERE serial_numbers = "mallet and simple articulated locomotives"