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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 intersect(self, other):
 """ Combine with another Region by performing intersection on their pixlists. Requires both regions to have the same maxdepth. Parameters other : :class:`AegeanTools.regions.Region` The region to be combined. """

        # work only on the lowest level
        # TODO: Allow this to be done for regions with different depths.
        if not (self.maxdepth == other.maxdepth): raise AssertionError("Regions must have the same maxdepth")
        self._demote_all()
        opd = set(other.get_demoted())
        self.pixeldict[self.maxdepth].intersection_update(opd)
        self._renorm()
        return