QMainWindowメモ

import sys
from PyQt5 import QtWidgets

app = QtWidgets.QApplication(sys.argv)
window = QtWidgets.QMainWindow()
window.show()
sys.exit(app.exec())

pyuic5 -o mainwindow.py mainwindow.ui

import sys
from PyQt5 import QtWidgets
from mainwindow import Ui_MainWindow

class MainWindow(QtWidgets.QMainWindow):
    def __init__(self, parent=None):
        super(MainWindow, self).__init__(parent)
        self.ui = Ui_MainWindow()
        self.ui.setupUi(self)

def main():
    app = QtWidgets.QApplication(sys.argv)
    window = MainWindow(None)
    window.show()
    sys.exit(app.exec())

if __name__ == '__main__':
    main()