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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 slot(self, slot_index, marshal=None, unmarshal=None, build=None, cast=None, compress=False):
 """ Decorator for use on classes derived from zlmdb.PersistentMap. The decorator define slots in a LMDB database schema based on persistent maps, and slot configuration. :param slot_index: :param marshal: :param unmarshal: :param build: :param cast: :param compress: :return: """


        def decorate(o):
            assert isinstance(o, PersistentMap)
            name = o.__class__.__name__
            assert slot_index not in self._index_to_slot
            assert name not in self._name_to_slot
            o._zlmdb_slot = slot_index
            o._zlmdb_marshal = marshal
            o._zlmdb_unmarshal = unmarshal
            o._zlmdb_build = build
            o._zlmdb_cast = cast
            o._zlmdb_compress = compress
            _slot = Slot(slot_index, name, o)
            self._index_to_slot[slot_index] = _slot
            self._name_to_slot[name] = _slot
            return o

        return decorate