text: 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_9 (callsign VARCHAR, on_air_id VARCHAR)
  ### Question:
  what is the callsign whtat uses 7bu?
  ### Answer:
  SELECT callsign FROM table_name_9 WHERE on_air_id = "7bu"