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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 next(self):
 """ Return the next row of a query result set, respecting if cursor was closed. """

        if self.rows is None:
            raise ProgrammingError(
                "No result available. " +
                "execute() or executemany() must be called first."
            )
        elif not self._closed:
            return next(self.rows)
        else:
            raise ProgrammingError("Cursor closed")