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_19 (year VARCHAR, class VARCHAR)
  ### Question:
  Which year has a railway class of 250?
  ### Answer:
  SELECT year FROM table_name_19 WHERE class = "250"