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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 convert_merge(builder, layer, input_names, output_names, keras_layer):
 """ Convert concat layer from keras to coreml. Parameters keras_layer: layer A keras layer object. builder: NeuralNetworkBuilder A neural network builder object. """

    # Get input and output names
    output_name = output_names[0]

    mode = _get_elementwise_name_from_keras_layer(keras_layer)
    builder.add_elementwise(name = layer, input_names = input_names,
            output_name = output_name, mode = mode)