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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 binary_value_or_stdin(value):
 """ Return fsencoded value or read raw data from stdin if value is None. """

    if value is None:
        reader = io.open(sys.stdin.fileno(), mode='rb', closefd=False)
        return reader.read()
    elif six.PY3:
        return os.fsencode(value)
    else:
        return value