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_26591309_2 (first_broadcast_uk___bbc_four__ VARCHAR, official_tns_gallup_ratings VARCHAR)
### Question:
When was the first UK broadcast for the episode with an official TNS Gallup rating of 1575000?
### Answer:
SELECT first_broadcast_uk___bbc_four__ FROM table_26591309_2 WHERE official_tns_gallup_ratings = 1575000