message: filter_values documentation fix
diff: @@ -68,7 +68,7 @@ def filter_values(column, default=None):
  Usage example:
  SELECT action, count(*) as times
  FROM logs
  - WHERE action in ( {{ "'" + "','".join(filter_values('action_type')) + "'" )
  + WHERE action in ( {{ "'" + "','".join(filter_values('action_type')) + "'" }} )
  GROUP BY 1
  :param column: column/filter name to lookup
  