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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 getinputencoding(stream=None):
 """Return preferred encoding for reading from ``stream``. ``stream`` defaults to sys.stdin. """

    if stream is None:
        stream = sys.stdin
    encoding = stream.encoding
    if not encoding:
        encoding = getpreferredencoding()
    return encoding