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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 seek_realtime(self, realtime):
 """Seek to a matching journal entry nearest to `timestamp` time. Argument `realtime` must be either an integer UNIX timestamp (in microseconds since the beginning of the UNIX epoch), or an float UNIX timestamp (in seconds since the beginning of the UNIX epoch), or a datetime.datetime instance. The integer form is deprecated. """

        if isinstance(realtime, _datetime.datetime):
            realtime = int(float(realtime.strftime("%s.%f")) * 1000000)
        elif not isinstance(realtime, int):
            realtime = int(realtime * 1000000)
        return super(Reader, self).seek_realtime(realtime)