template for quickly loading your Qt Designer UI files for your python applications.

python qt gui loader master.py

import sys
from qtpy import uic, QtWidgets, QtCore, QtGui

class MainWindow(QtWidgets.QMainWindow):
    def __init__(self):
        super(MainWindow, self).__init__()
        # save your ui file in same directory and put filename below
        uic.loadUi('your_ui_file.ui', self)
        self.show()


if __name__ == '__main__':
    app = QtWidgets.QApplication(sys.argv)
    window = MainWindow()
    sys.exit(app.exec_())