'Reimplement Qt method'

def mousePressEvent(self, event):

    if (event.button() != Qt.LeftButton):
        QTableView.mousePressEvent(self, event)
        return
    index_clicked = self.indexAt(event.pos())
    if index_clicked.isValid():
        if ((index_clicked == self.currentIndex()) and (index_clicked in self.selectedIndexes())):
            self.clearSelection()
        else:
            QTableView.mousePressEvent(self, event)
    else:
        self.clearSelection()
        event.accept()
