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 singer_in_concert (concert_id VARCHAR); CREATE TABLE concert (concert_name VARCHAR, theme VARCHAR, concert_id VARCHAR)
  ### Question:
  What are the names , themes , and number of singers for every concert ?
  ### Answer:
  SELECT t2.concert_name, t2.theme, COUNT(*) FROM singer_in_concert AS t1 JOIN concert AS t2 ON t1.concert_id = t2.concert_id GROUP BY t2.concert_id