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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 imdecode(buf, *args, **kwargs):
 """Decode an image to an NDArray. .. note:: `imdecode` uses OpenCV (not the CV2 Python library). MXNet must have been built with USE_OPENCV=1 for `imdecode` to work. Parameters buf : str/bytes/bytearray or numpy.ndarray Binary image data as string or numpy ndarray. flag : int, optional, default=1 1 for three channel color output. 0 for grayscale output. to_rgb : int, optional, default=1 1 for RGB formatted output (MXNet default). 0 for BGR formatted output (OpenCV default). out : NDArray, optional Output buffer. Use `None` for automatic allocation. Returns ------- NDArray An `NDArray` containing the image. Example ------- <NDArray 224x224x3 @cpu(0)> Set `flag` parameter to 0 to get grayscale output <NDArray 224x224x1 @cpu(0)> Set `to_rgb` parameter to 0 to get output in OpenCV format (BGR) <NDArray 224x224x3 @cpu(0)> """

    if not isinstance(buf, nd.NDArray):
        if sys.version_info[0] == 3 and not isinstance(buf, (bytes, bytearray, np.ndarray)):
            raise ValueError('buf must be of type bytes, bytearray or numpy.ndarray,'
                             'if you would like to input type str, please convert to bytes')
        buf = nd.array(np.frombuffer(buf, dtype=np.uint8), dtype=np.uint8)

    return _internal._cvimdecode(buf, *args, **kwargs)