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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_batchnorm(builder, layer, input_names, output_names, keras_layer):
 """ Convert a Batch Normalization layer. Parameters keras_layer: layer A keras layer object. builder: NeuralNetworkBuilder A neural network builder object. """


    # Get input and output names
    input_name, output_name = (input_names[0], output_names[0])

    axis = keras_layer.axis
    nb_channels = keras_layer.input_shape[axis]

    # Set parameters
    # Parameter arrangement in Keras: gamma, beta, mean, variance
    idx = 0
    gamma, beta = None, None
    if keras_layer.scale:
        gamma = keras_layer.get_weights()[idx]
        idx += 1
    if keras_layer.center:
        beta = keras_layer.get_weights()[idx]
        idx += 1
    mean = keras_layer.get_weights()[idx]
    std = keras_layer.get_weights()[idx+1]

    gamma = _np.ones(mean.shape) if gamma is None else gamma
    beta = _np.zeros(mean.shape) if beta is None else beta

    # compute adjusted parameters
    variance = std * std
    f = 1.0 / _np.sqrt(std + keras_layer.epsilon)
    gamma1 = gamma*f
    beta1 = beta - gamma*mean*f
    mean[:] = 0.0 #mean
    variance[:] = 1.0 - .00001 #stddev

    builder.add_batchnorm(
        name = layer,
        channels = nb_channels,
        gamma = gamma1,
        beta = beta1,
        mean = mean,
        variance = variance,
        input_name = input_name,
        output_name = output_name)