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 stadium (country VARCHAR, opening_year INTEGER)
  ### Question:
  Which countries do not have a stadium that was opened after 2006?
  ### Answer:
  SELECT country FROM stadium EXCEPT SELECT country FROM stadium WHERE opening_year > 2006