How many networks are there that have a channel number 7?
CREATE TABLE table_160728_4 (network VARCHAR, channel VARCHAR)
SELECT COUNT(network) FROM table_160728_4 WHERE channel = 7
### Context: CREATE TABLE table_160728_4 (network VARCHAR, channel VARCHAR) ### Question: How many networks are there that have a channel number 7? ### Answer: SELECT COUNT(network) FROM table_160728_4 WHERE channel = 7