What is the 2004 population for ?
CREATE TABLE table_43597 (
    "Name" text,
    "Hanzi" text,
    "Hanyu Pinyin" text,
    "Population (2004 est.)" text,
    "Area (km\u00b2)" text,
    "Density (/km\u00b2)" text
)
SELECT "Population (2004 est.)" FROM table_43597 WHERE "Hanzi" = '山海关区'
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 2004 population for ? ### Input: CREATE TABLE table_43597 (
    "Name" text,
    "Hanzi" text,
    "Hanyu Pinyin" text,
    "Population (2004 est.)" text,
    "Area (km\u00b2)" text,
    "Density (/km\u00b2)" text
) ### Response: SELECT "Population (2004 est.)" FROM table_43597 WHERE "Hanzi" = '山海关区'