蟒蛇全局变量未能在类分配

Question

我正在使用python和PyQt5构建软件。单击“设置”时，将弹出“设置”窗口（直到可以正常工作为止）。然后，我希望能保存在一个全局变量（通过QLineEdit的）用户输入值，但分配没有成功。分配后的打印，打印方法给了我2个不同的输出。 （期望它们是相同的）

def openSettingWindow(self):  
    global grav_used
    global airden_used
    self.window_setting = QDialog()
    self.ui_setting = Ui_SettingWindow()
    self.ui_setting.setupUi(self.window_setting)
    self.window_setting.show()
    self.ui_setting.lineEdit_g.setText(grav_used) #Set default gravity acceleration g value to 9.81m/s^2
    self.ui_setting.lineEdit_airDen.setText(airden_used) #Set default air density value to 1.226kg/m^3

    grav_used=self.ui_setting.lineEdit_g.text()
    airden_used=self.ui_setting.lineEdit_airDen.text()

    self.ui_setting.pushButton_settingOK.clicked.connect(lambda: print (self.ui_setting.lineEdit_airDen.text(),airden_used))