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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 _massageData(self, row):
 """ Convert a row into a tuple of Item instances, by slicing it according to the number of columns for each instance, and then proceeding as for ItemQuery._massageData. @param row: an n-tuple, where n is the total number of columns specified by all the item types in this query. @return: a tuple of instances of the types specified by this query. """

        offset = 0
        resultBits = []

        for i, tableClass in enumerate(self.tableClass):
            numAttrs = self.schemaLengths[i]

            result = self.store._loadedItem(self.tableClass[i],
                                            row[offset],
                                            row[offset+1:offset+numAttrs])
            assert result.store is not None, "result %r has funky store" % (result,)
            resultBits.append(result)

            offset += numAttrs

        return tuple(resultBits)