code: def test_skip_optimization_expr():
      src_vec = single_column_frame()
      data = square_matrix(src_vec.nrow)
  
      def get_expr():
          return ExprNode(
              "cols_py",
              ExprNode("append", data, src_vec, "dummy_name"),
              1,
          )
  
      (expr, _) = _assert_expr_results_eq(get_expr)
  
      assert expr._op == "cols_py"
      assert expr.arg(0) == data._ex and expr.arg(1) == 1
  
file_path: h2o-3/h2o-py/tests/testdir_misc/pyunit_expr_optimizations.py
imports: import h2o
  import sys
  from tests import pyunit_utils
  from h2o import H2OFrame
  from h2o.expr import ExprNode
label_desc: Use image node_id 7 for calling a global function with example usage: test_skip_optimization_expr() and returns: ExprNode