Which Week has a Result of w 20-13?
CREATE TABLE table_45718 (
    "Week" real,
    "Date" text,
    "Opponent" text,
    "Result" text,
    "Attendance" real
)
SELECT AVG("Week") FROM table_45718 WHERE "Result" = 'w 20-13'
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 Week has a Result of w 20-13? ### Input: CREATE TABLE table_45718 (
    "Week" real,
    "Date" text,
    "Opponent" text,
    "Result" text,
    "Attendance" real
) ### Response: SELECT AVG("Week") FROM table_45718 WHERE "Result" = 'w 20-13'