#  create tab2 layout
grid = QGridLayout()
        for i in range(1, 15):
            for j in range(1, 4):
                grid.addWidget(QLabel(str(i) + str(j)), i, j)
        self.tab2widget.setLayout(grid)

#  resize and realign tab2 layout
        for label in self.tab2widget.children():
            if isinstance(label, QLabel):
                label.setAlignment(Qt.AlignmentFlag.AlignCenter

#  resize and realign tab2 layout
        for label in self.tab2widget.children():
            if isinstance(label, QLabel):
                label.setAlignment(Qt.AlignmentFlag.AlignCenter)

#  apply something to all items in grid
        self.index = 0
        while self.index < 42:
            grid.itemAt(self.index).widget().setStyleSheet("QLabel {background-color: yellow;}")
            self.index = self.index + 1

#  layout positioning by setFixedSize of 1st widget in each row
        self.grid_index = 0
        while self.grid_index < 42:
            grid.itemAt(self.grid_index).widget().setFixedSize(229, 13)
            grid.itemAt(self.grid_index+3).widget().setFixedSize(229, 227)
            self.grid_index = self.grid_index + 6