class_docstr: NodeRepr test
code: def test_raise_op(self):
      node_input = {
          "inputs": ("a", "b"),
          "outputs": ("a", "b"),
          "iter_info": {"type": "map", "param": None},
      }
      with self.assertRaises(ValidationError):
          NodeRepr(uid="test_op", **node_input)
  
imports: import unittest
  from pydantic import ValidationError
  from towhee.runtime.node_repr import NodeRepr
label_desc: Use image node_id 3 for calling the TestNodeRepr obj's underlying member method code with example usage: obj.test_raise_op() without return types