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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 _time_from_iso8601_time_naive(value):
 """Convert a zoneless ISO8601 time string to naive datetime time :type value: str :param value: The time string to convert :rtype: :class:`datetime.time` :returns: A datetime time object created from the string :raises ValueError: if the value does not match a known format. """

    if len(value) == 8:  # HH:MM:SS
        fmt = _TIMEONLY_NO_FRACTION
    elif len(value) == 15:  # HH:MM:SS.micros
        fmt = _TIMEONLY_W_MICROS
    else:
        raise ValueError("Unknown time format: {}".format(value))
    return datetime.datetime.strptime(value, fmt).time()