class Tree(QtWidgets.QTreeWidget):
    # ...

    def dropEvent(self, event):
        if event.source() == self:
            event.setDropAction(QtCore.Qt.MoveAction)
            super().dropEvent(event)
        elif isinstance(event.source(), QtWidgets.QListWidget):
            item = self.itemAt(event.pos())
            ix = self.indexAt(event.pos())
            col = 0 if item is None else ix.column()
            item = self.invisibleRootItem() if item is None else item            
            ba = event.mimeData().data('application/x-qabstractitemmodeldatalist')
            data_items = decode_data(ba)
            for data_item in data_items:
                it = QtWidgets.QTreeWidgetItem()
                item.addChild(it)
                for data in data_items:
                    for r, v in data.items():
                        it.setData(col, r, v)

class List(QtWidgets.QListWidget):
    # ... 

    def dropEvent(self, event):
        if event.source() == self:
            event.setDropAction(QtCore.Qt.MoveAction)
            QtWidgets.QListWidget.dropEvent(self, event)
        elif isinstance(event.source(), QtWidgets.QTreeWidget):
            item = self.itemAt(event.pos())
            row = self.row(item) if item else self.count()
            ba = event.mimeData().data('application/x-qabstractitemmodeldatalist')
            data_items = decode_data(ba)
            for i, data_item in enumerate(data_items):
                it = QtWidgets.QListWidgetItem()
                self.insertItem(row+i, it)
                for r, v in data_item.items():
                    it.setData(r,v)