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_57 (president VARCHAR, c_span_2009 VARCHAR)
  ### Question:
  Who is the president when c-span 2009 is 21?
  ### Answer:
  SELECT president FROM table_name_57 WHERE c_span_2009 = "21"