Which season has a Staffel E of Stahl Riesa?
CREATE TABLE table_name_21 (
    season VARCHAR,
    staffel_e VARCHAR
)
SELECT season FROM table_name_21 WHERE staffel_e = "stahl riesa"
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: Which season has a Staffel E of Stahl Riesa? ### Input: CREATE TABLE table_name_21 (
    season VARCHAR,
    staffel_e VARCHAR
) ### Response: SELECT season FROM table_name_21 WHERE staffel_e = "stahl riesa"