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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 unmap_by_address(self, absolute_address):
 """ Removes a mapping based on its absolute address. :param absolute_address: An absolute address """


        desc = self._address_to_region_id[absolute_address]
        del self._address_to_region_id[absolute_address]
        del self._region_id_to_address[desc.region_id]