如何在pyqt中对齐右下角的按钮？

import sys
from PyQt5.QtWidgets import QApplication, QMainWindow, QWidget, QVBoxLayout, QHBoxLayout, QPushButton, QGridLayout

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

        # 创建主窗口布局管理器
        layout = QVBoxLayout()

        # 创建容器和网格布局
        container = QWidget()
        grid_layout = QGridLayout(container)

        # 创建按钮并添加到网格布局
        button1 = QPushButton("Button 1")
        button2 = QPushButton("Button 2")
        grid_layout.addWidget(button1, 0, 0)
        grid_layout.addWidget(button2, 1, 0)

        # 将容器添加到主窗口布局管理器
        layout.addWidget(container, 1)

        # 添加弹簧到主窗口布局管理器
        layout.addStretch(0)

        # 设置主窗口布局管理器
        central_widget = QWidget()
        central_widget.setLayout(layout)
        self.setCentralWidget(central_widget)

if __name__ == "__main__":
    app = QApplication(sys.argv)
    window = MainWindow()
    window.show()
    sys.exit(app.exec_())