Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE table_name_56 (opposition VARCHAR, stadium VARCHAR, attendance VARCHAR)
### Question:
Who's the opposition at westpac stadium when the attendance is 31,853?
### Answer:
SELECT opposition FROM table_name_56 WHERE stadium = "westpac stadium" AND attendance = "31,853"