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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 write_if_different(filename, data):
 """Write `data` to `filename`, if the content of the file is different. Parameters filename : str The file name to be written to. data : bytes The data to be written to `filename`. """


    assert isinstance(data, bytes)

    if os.path.exists(filename):
        with open(filename, 'rb') as fd:
            original_data = fd.read()
    else:
        original_data = None

    if original_data != data:
        with open(filename, 'wb') as fd:
            fd.write(data)