from PyQt4 import QtCore, QtGui

class A(object):
	def X(self,n):
		for i in range(n):
			pass
		M().widget.hide()
		M().widget_2.show()
		
		
class M(object):
	
	def s1(self):
		A().X(1000)
		
	def s2(self):
		self.widget_2.hide()
		self.widget.show()
		
	def setupUi(self, mainWindow):
		mainWindow.setObjectName("mainWindow")
		mainWindow.setEnabled(True)
		mainWindow.resize(300, 300)
		mainWindow.setMinimumSize(QtCore.QSize(300, 300))
		mainWindow.setMaximumSize(QtCore.QSize(300, 300))
		mainWindow.setBaseSize(QtCore.QSize(300, 300))
		icon = QtGui.QIcon()
		icon.addPixmap(QtGui.QPixmap("ico.png"), QtGui.QIcon.Normal, QtGui.QIcon.Off)
		mainWindow.setWindowIcon(icon)
		self.centralwidget = QtGui.QWidget(mainWindow)
		self.centralwidget.setObjectName("centralwidget")
		self.widget = QtGui.QWidget(self.centralwidget)
		self.widget.setGeometry(QtCore.QRect(0, 0, 300, 300))
		self.widget.setObjectName("widget")
		self.pushButton = QtGui.QPushButton(self.widget)
		self.pushButton.setGeometry(QtCore.QRect(100, 100, 100, 30))
		self.pushButton.setObjectName("pushButton")
		self.widget_2 = QtGui.QWidget(self.centralwidget)
		self.widget_2.setGeometry(QtCore.QRect(0, 0, 300, 300))
		self.widget_2.setObjectName("widget")
		self.pushButton_2 = QtGui.QPushButton(self.widget_2)
		self.pushButton_2.setGeometry(QtCore.QRect(100, 150, 100, 30))
		self.pushButton_2.setObjectName("pushButton_2")
		mainWindow.setCentralWidget(self.centralwidget)
		self.widget_2.hide()

		self.retranslateUi(mainWindow)
		
		QtCore.QObject.connect(self.pushButton, QtCore.SIGNAL("pressed()"), self.s1)
		QtCore.QObject.connect(self.pushButton_2, QtCore.SIGNAL("pressed()"), self.s2)


	def retranslateUi(self, mainWindow):
		self.pushButton.setText(QtGui.QApplication.translate("mainWindow", "1", None, QtGui.QApplication.UnicodeUTF8))
		self.pushButton_2.setText(QtGui.QApplication.translate("mainWindow", "2", None, QtGui.QApplication.UnicodeUTF8))


if __name__ == "__main__":
	import sys
	
	app = QtGui.QApplication(sys.argv)
	MainWindow = QtGui.QMainWindow()
	ui = M()
	ui.setupUi(MainWindow)
	MainWindow.show()
	sys.exit(app.exec_())

        M().widget.hide()
        M().widget_2.show()