def deleteChunk(self, cx, cz, batch=None):
        """
        Deletes a chunk at given cx, cz. Deletes using the batch if batch is given, uses world_db() otherwise.
        :param cx, cz Coordinates of the chunk
        :param batch WriteBatch
        :return: None
        """
        self.worldFile.deleteChunk(cx, cz, batch=batch)
        try:
            del self._loadedChunks[(cx, cz)]
        except:
            pass
        try:
            self.allChunks.remove((cx, cz))
        except:
            pass

        Deletes a chunk at given cx, cz. Deletes using the batch if batch is given, uses world_db() otherwise.
        :param cx, cz Coordinates of the chunk
        :param batch WriteBatch
        :return: None
        
pymclevel/leveldbpocket.py