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_21781578_2 (season_no VARCHAR, us_viewers__millions_ VARCHAR)
### Question:
What was the number of season number entries that had US Viewers of 12.30 million?
### Answer:
SELECT COUNT(season_no) FROM table_21781578_2 WHERE us_viewers__millions_ = "12.30"