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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 reset_stream(stream):
 """Reset stream pointer to the first element. If stream is not seekable raise Exception. """

    try:
        position = stream.tell()
    except Exception:
        position = True
    if position != 0:
        try:
            stream.seek(0)
        except Exception:
            message = 'It\'s not possible to reset this stream'
            raise exceptions.TabulatorException(message)