What stage number had the general classification Rory Sutherland?
CREATE TABLE table_23157997_13 (
    stage VARCHAR,
    general_classification VARCHAR
)
SELECT COUNT(stage) FROM table_23157997_13 WHERE general_classification = "Rory Sutherland"
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 stage number had the general classification Rory Sutherland? ### Input: CREATE TABLE table_23157997_13 (
    stage VARCHAR,
    general_classification VARCHAR
) ### Response: SELECT COUNT(stage) FROM table_23157997_13 WHERE general_classification = "Rory Sutherland"