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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 enumerate(self, name, start=1):
 """ Enumerates all rows such that the pseudo key and the ordinal number are a unique key. :param str name: The key holding the ordinal number. :param int start: The start of the ordinal numbers. Foreach pseudo key the first row has this ordinal number. """

        for pseudo_key, rows in self._rows.items():
            rows = self._rows_sort(rows)
            ordinal = start
            for row in rows:
                row[name] = ordinal
                ordinal += 1
            self._rows[pseudo_key] = rows