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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 interpolate(self, times, proj=PlateCarree()) -> np.ndarray: """Interpolates a trajectory in time. """

        if proj not in self.interpolator:
            self.interpolator[proj] = interp1d(
                np.stack(t.to_pydatetime().timestamp() for t in self.timestamp),
                proj.transform_points(
                    PlateCarree(), *np.stack(self.coords).T
                ).T,
            )
        return PlateCarree().transform_points(
            proj, *self.interpolator[proj](times)
        )