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_73 (tournament VARCHAR, career_sr VARCHAR)
### Question:
What is Tournament, when Career SR is "ATP Masters Series"?
### Answer:
SELECT tournament FROM table_name_73 WHERE career_sr = "atp masters series"