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_11900378_1 (doubles_champions VARCHAR, tournament VARCHAR)
### Question:
How many doubles champions were there for the Serbia f6 Futures tournament?
### Answer:
SELECT COUNT(doubles_champions) FROM table_11900378_1 WHERE tournament = "Serbia F6 Futures"