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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 remove_row(self, row_num=None):
 """ Remove a row from the grid """

        #DeleteRows(self, pos, numRows, updateLabel
        if not row_num and row_num != 0:
            row_num = self.GetNumberRows() - 1
        label = self.GetCellValue(row_num, 0)
        self.DeleteRows(pos=row_num, numRows=1, updateLabels=True)

        # remove label from row_labels
        try:
            self.row_labels.remove(label)
        except ValueError:
            # if label name hasn't been saved yet, simply truncate row_labels
            self.row_labels = self.row_labels[:-1]
        self.row_items.pop(row_num)
        if not self.changes:
            self.changes = set()
        self.changes.add(-1)
        # fix #s for rows edited:
        self.update_changes_after_row_delete(row_num)