What days are vacant that were replaced by john brown?
CREATE TABLE table_11207040_6 (
    date_of_vacancy VARCHAR,
    replaced_by VARCHAR
)
SELECT date_of_vacancy FROM table_11207040_6 WHERE replaced_by = "John Brown"
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 days are vacant that were replaced by john brown? ### Input: CREATE TABLE table_11207040_6 (
    date_of_vacancy VARCHAR,
    replaced_by VARCHAR
) ### Response: SELECT date_of_vacancy FROM table_11207040_6 WHERE replaced_by = "John Brown"