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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_mean(binaryproto_fname, output=None):
 """Convert caffe mean Parameters binaryproto_fname : str Filename of the mean output : str, optional Save the mean into mxnet's format Returns ------- NDArray Mean in ndarray """

    mean_blob = caffe_parser.caffe_pb2.BlobProto()
    with open(binaryproto_fname, 'rb') as f:
        mean_blob.ParseFromString(f.read())

    img_mean_np = np.array(mean_blob.data)
    img_mean_np = img_mean_np.reshape(
        mean_blob.channels, mean_blob.height, mean_blob.width
    )
    # swap channels from Caffe BGR to RGB
    img_mean_np[[0, 2], :, :] = img_mean_np[[2, 0], :, :]
    nd = mx.nd.array(img_mean_np)
    if output is not None:
        mx.nd.save(output, {"mean_image": nd})
    return nd