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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 _update_rows(self):
 """ Update the row and column numbers of child items. """

        for row, item in enumerate(self._items):
            item.row = row  # Row is the Parent item
            item.column = 0
        
        for column, item in enumerate(self._columns):
            item.row = self.row  # Row is the Parent item
            item.column = column