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_1305623_20 (silver_medals VARCHAR, ensemble VARCHAR)
### Question:
How many numbers were listed under Silver Medals for Portsmouth HS?
### Answer:
SELECT COUNT(silver_medals) FROM table_1305623_20 WHERE ensemble = "Portsmouth HS"