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_62 (silver INTEGER, gold VARCHAR)
### Question:
How many silver medals did the country that won 20 gold medals win in the 1955 Pan American Games?
### Answer:
SELECT SUM(silver) FROM table_name_62 WHERE gold = 20