如何合并qtable行的两个单元格？

from PyQt5.QtWidgets import QApplication, QTableView, QStyledItemDelegate, QStyleOptionViewItem, QStyle, QWidget, QHBoxLayout
from PyQt5.QtCore import Qt, QModelIndex

class MergeDelegate(QStyledItemDelegate):
    def paint(self, painter, option, index):
        if index.column() == 0:
            # 获取当前单元格的数据
            data = index.data(Qt.DisplayRole)
            # 获取下一个单元格的数据
            next_data = index.sibling(index.row() + 1, index.column()).data(Qt.DisplayRole)
            # 判断两个单元格的数据是否相同
            if data == next_data:
                # 获取当前单元格的区域
                rect = option.rect
                # 绘制合并后的单元格
                painter.save()
                painter.setRenderHint(QPainter.Antialiasing)
                painter.setPen(Qt.NoPen)
                painter.setBrush(option.backgroundBrush)
                painter.drawRect(rect)
                painter.setPen(option.palette.color(QPalette.Text))
                painter.drawText(rect, Qt.AlignCenter, data)
                painter.restore()
                return

        # 默认绘制
        super().paint(painter, option, index)

class MainWindow(QWidget):
    def __init__(self):
        super().__init__()

        self.table_view = QTableView(self)
        self.table_view.setItemDelegateForColumn(0, MergeDelegate())

        # 创建数据模型和填充数据
        self.model = QStandardItemModel(4, 2)
        self.model.setData(self.model.index(0, 0), "A")
        self.model.setData(self.model.index(1, 0), "A")
        self.model.setData(self.model.index(2, 0), "B")
        self.model.setData(self.model.index(3, 0), "C")
        self.model.setData(self.model.index(0, 1), "1")
        self.model.setData(self.model.index(1, 1), "2")
        self.model.setData(self.model.index(2, 1), "3")
        self.model.setData(self.model.index(3, 1), "4")

        self.table_view.setModel(self.model)

        layout = QHBoxLayout(self)
        layout.addWidget(self.table_view)

if __name__ == '__main__':
    app = QApplication([])
    window = MainWindow()
    window.show()
    app.exec_()