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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 _setsizes(self, cursor=None):
 """Set stored input and output sizes for cursor execution."""

        if cursor is None:
            cursor = self._cursor
        if self._inputsizes:
            cursor.setinputsizes(self._inputsizes)
        for column, size in self._outputsizes.items():
            if column is None:
                cursor.setoutputsize(size)
            else:
                cursor.setoutputsize(size, column)