what was the only year keene won class aa ?
CREATE TABLE table_204_133 (
    id number,
    "school year" text,
    "class a" text,
    "class aa" text,
    "class aaa" text,
    "class aaaa" text,
    "class aaaaa" text
)
SELECT "school year" FROM table_204_133 WHERE "class aa" = 'keene'
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 was the only year keene won class aa ? ### Input: CREATE TABLE table_204_133 (
    id number,
    "school year" text,
    "class a" text,
    "class aa" text,
    "class aaa" text,
    "class aaaa" text,
    "class aaaaa" text
) ### Response: SELECT "school year" FROM table_204_133 WHERE "class aa" = 'keene'