SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 1)
    Function arrayReduce (children 1)
     ExpressionList (children 3)
      Literal \'simpleLinearRegression\'
      Literal Array_[UInt64_3, UInt64_3]
      Literal Array_[UInt64_3, UInt64_4]