What type has rest day as a course and was on 21 may?
CREATE TABLE table_57018 (
    "Date" text,
    "Course" text,
    "Distance" text,
    "Type" text,
    "Winner" text
)
SELECT "Type" FROM table_57018 WHERE "Course" = 'rest day' AND "Date" = '21 may'
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 type has rest day as a course and was on 21 may? ### Input: CREATE TABLE table_57018 (
    "Date" text,
    "Course" text,
    "Distance" text,
    "Type" text,
    "Winner" text
) ### Response: SELECT "Type" FROM table_57018 WHERE "Course" = 'rest day' AND "Date" = '21 may'