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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def clone_g0_inputs_on_ngpus(self, inputs, outputs, g0_inputs):
 """ Clone variables unused by the attack on all GPUs. Specifically, the ground-truth label, y, has to be preserved until the training step. :param inputs: A list of dictionaries as the inputs to each step. :param outputs: A list of dictionaries as the outputs of each step. :param g0_inputs: Initial variables to be cloned. :return: Updated inputs and outputs. """

    assert len(inputs) == len(outputs), (
        'Inputs and outputs should have the same number of elements.')

    inputs[0].update(g0_inputs)
    outputs[0].update(g0_inputs)

    # Copy g0_inputs forward
    for i in range(1, len(inputs)):
      # Create the graph for i'th step of attack
      device_name = inputs[i]['x'].device
      with tf.device(device_name):
        with tf.variable_scope('step%d' % i):
          for k, v in g0_inputs.iteritems():
            if k not in inputs[i]:
              v_copy = clone_variable(k, v)
              inputs[i][k] = v_copy
              outputs[i][k] = v_copy

    return inputs, outputs