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_95 (sets VARCHAR, nadal VARCHAR, federer VARCHAR)
### Question:
What were the sets when Federer had 6 and a nadal of 13?
### Answer:
SELECT sets FROM table_name_95 WHERE nadal = 13 AND federer = 6