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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 xy_time(self) -> Iterator[Tuple[float, float, float]]: """Iterates on longitudes, latitudes and timestamps."""

        iterator = iter(zip(self.coords, self.timestamp))
        while True:
            next_ = next(iterator, None)
            if next_ is None:
                return
            coords, time = next_
            yield (coords[0], coords[1], time.to_pydatetime().timestamp())