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