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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 add_point(self, reading_id, uptime=None, utc=None, is_break=False):
 """Add a time point that could be used as a UTC reference."""


        if reading_id == 0:
            return

        if uptime is None and utc is None:
            return

        if uptime is not None and uptime & (1 << 31):
            if utc is not None:
                return

            uptime &= ~(1 << 31)

            utc = self.convert_rtc(uptime)
            uptime = None

        anchor = _TimeAnchor(reading_id, uptime, utc, is_break, exact=utc is not None)

        if anchor in self._anchor_points:
            return

        self._anchor_points.add(anchor)
        self._prepared = False