class_docstr: Test ops
code: def test_local(self):
      # pylint: disable=protected-access
      op = ops.local.add_operator(10)
      self.assertEqual(op._op, None)
      res = op(2)
      self.assertNotEqual(op._op, None)
      self.assertEqual(op.name, "local/add-operator")
      self.assertEqual(op.init_args, (10,))
      self.assertEqual(op.init_kws, {})
      self.assertEqual(op.tag, "main")
      self.assertEqual(res.sum, 12)
  
file_path: towhee/tests/unittests/runtime/test_factory.py
imports: import unittest
  from towhee.runtime import ops, register
label_desc: Use image node_id 4 for calling the TestOps obj's underlying member method code with example usage: obj.test_local() without return types