code: def test_valid_naming(self):
      OpWithMultipleOutputs(name="test_op")
  
      with self.assertRaisesRegex(
          ValueError,
          "must be a string and cannot contain character `/`.",
      ):
          OpWithMultipleOutputs(name="test/op")
  
imports: import numpy
  from keras import backend
  from keras import testing
  from keras.backend.common import keras_tensor
  from keras.ops import numpy
  from keras.ops import operation
label_desc: Use image node_id 6 for calling the OperationTest obj's underlying member method code with example usage: obj.test_valid_naming() without return types