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_17 (song_sung VARCHAR, artist VARCHAR, week VARCHAR)
### Question:
Which song was sung by Artist Luther Vandross in the Week Top 20?
### Answer:
SELECT song_sung FROM table_name_17 WHERE artist = "luther vandross" AND week = "top 20"