som

from PyQt5 import QtWidgets, uic
from PyQt5.QtWidgets import QApplication, QWidget
import sys

Form, Window = uic.loadUiType("1.ui")


class App(QWidget):
    def __init__(self):
        self.ui = uic.loadUi("1.ui")
        self.start()

    def start(self):
        self.ui.show()
        self.set()

    def set(self):
        self.btn1.clicked.connect(self.button_clicked)

    def button_clicked(self):
        self.label.setText("you pressed the button")
        self.update()

    def update(self):
        self.label.adjustSize()


def window():
    app = QApplication([])
    window = Window()
    form = Form()
    form.setupUi(window)
    window.show()
    sys.exit(app.exec_())


window()