SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 1)
    Function flatten (children 1)
     ExpressionList (children 1)
      Function array (children 1)
       ExpressionList (children 1)
        Function array (children 1)
         ExpressionList (children 1)
          Function array (children 1)
           ExpressionList