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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 to_time(wmi_time):
 """Convenience wrapper to take a WMI datetime string of the form yyyymmddHHMMSS.mmmmmm+UUU and return a 9-tuple containing the individual elements, or None where string contains placeholder stars. :param wmi_time: The WMI datetime string in `yyyymmddHHMMSS.mmmmmm+UUU` format :returns: A 9-tuple of (year, month, day, hours, minutes, seconds, microseconds, timezone) """


    def int_or_none(s, start, end):
        try:
            return int(s[start:end])
        except ValueError:
            return None

    year = int_or_none(wmi_time, 0, 4)
    month = int_or_none(wmi_time, 4, 6)
    day = int_or_none(wmi_time, 6, 8)
    hours = int_or_none(wmi_time, 8, 10)
    minutes = int_or_none(wmi_time, 10, 12)
    seconds = int_or_none(wmi_time, 12, 14)
    microseconds = int_or_none(wmi_time, 15, 21)
    timezone = wmi_time[22:]

    if timezone == "***":
        timezone = None

    return year, month, day, hours, minutes, seconds, microseconds, timezone