“Múltiples páginas UI dentro de la misma ventana ui pyqt” Código de respuesta

Múltiples páginas UI dentro de la misma ventana ui pyqt

from PyQt5.QtWidgets import (QWidget, QPushButton,
    QHBoxLayout, QVBoxLayout, QApplication, QStackedWidget, QLabel)

class Example(QWidget):

    def __init__(self):
        super().__init__()
        self.initUI()
        self.stacked_widget.currentChanged.connect(self.set_button_state)
        self.next_button.clicked.connect(self.next_page)
        self.prev_button.clicked.connect(self.prev_page)


    def initUI(self):

        self.next_button = QPushButton('Next')
        self.prev_button = QPushButton('Previous')
        self.next_button.setEnabled(False)
        self.prev_button.setEnabled(False)
        self.stacked_widget = QStackedWidget()

        hbox = QHBoxLayout()
        hbox.addStretch(1)
        hbox.addWidget(self.prev_button)
        hbox.addWidget(self.next_button)

        vbox = QVBoxLayout()
        vbox.addWidget(self.stacked_widget)
        vbox.addLayout(hbox)

        self.setLayout(vbox)


    def set_button_state(self, index):
        self.prev_button.setEnabled(index > 0)
        n_pages = len(self.stacked_widget)
        self.next_button.setEnabled( index % n_pages < n_pages - 1)

    def insert_page(self, widget, index=-1):
        self.stacked_widget.insertWidget(index, widget)
        self.set_button_state(self.stacked_widget.currentIndex())

    def next_page(self):
        new_index = self.stacked_widget.currentIndex()+1
        if new_index < len(self.stacked_widget):
            self.stacked_widget.setCurrentIndex(new_index)

    def prev_page(self):
        new_index = self.stacked_widget.currentIndex()-1
        if new_index >= 0:
            self.stacked_widget.setCurrentIndex(new_index)

if __name__ == '__main__':

    app = QApplication([])
    ex = Example()
    for i in range(5):
        ex.insert_page(QLabel(f'This is page {i+1}'))
    ex.resize(400,300)
    ex.show()
    app.exec()