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_21584646_10 (champion VARCHAR, runner_up VARCHAR)
### Question:
How many champions are shown for the runner-up of stefan edberg?
### Answer:
SELECT COUNT(champion) FROM table_21584646_10 WHERE runner_up = "Stefan Edberg"