Who is the opposing team when the game was played on the Shea Stadium?
CREATE TABLE table_21665 (
    "Week" real,
    "Date" text,
    "Opponent" text,
    "Stadium" text,
    "Result" text,
    "Record" text,
    "Streak" text,
    "Attendance" real
)
SELECT "Opponent" FROM table_21665 WHERE "Stadium" = 'Shea Stadium'
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: Who is the opposing team when the game was played on the Shea Stadium? ### Input: CREATE TABLE table_21665 (
    "Week" real,
    "Date" text,
    "Opponent" text,
    "Stadium" text,
    "Result" text,
    "Record" text,
    "Streak" text,
    "Attendance" real
) ### Response: SELECT "Opponent" FROM table_21665 WHERE "Stadium" = 'Shea Stadium'