def convert_softmax(builder, layer, input_names, output_names, keras_layer):
    """Convert a softmax layer from keras to coreml.

    Parameters
    keras_layer: layer
    ----------
        A keras layer object.

    builder: NeuralNetworkBuilder
        A neural network builder object.
    """
    input_name, output_name = (input_names[0], output_names[0])

    builder.add_softmax(name = layer, input_name = input_name,
            output_name = output_name)