import sys
              from PyQt5 import QtWidgets

              def basicWindow():
                  app = QtWidgets.QApplication(sys.argv)
                  windowExample = QtWidgets.QWidget()
                  windowExample.setWindowTitle('Basic Window Example')
                  windowExample.show()
                  sys.exit(app.exec_())

              basicWindow()

PyQt5 Change Window Size

              import sys
              from PyQt5 import QtWidgets

              def basicWindow():
                  app = QtWidgets.QApplication(sys.argv)
                  windowExample = QtWidgets.QWidget()
                  windowExample.setGeometry(0, 0, 400, 400)
                  windowExample.setWindowTitle('Basic Window Example')
                  windowExample.show()
                  sys.exit(app.exec_())

              basicWindow()

PyQt5 Add Window Icon

import sys
from PyQt5 import QtWidgets, QtGui

def basicWindow():
    app = QtWidgets.QApplication(sys.argv)
    windowExample = QtWidgets.QWidget()
    windowExample.setWindowTitle('Basic Window Example')
    windowExample.setWindowIcon(QtGui.QIcon("python.jpg"))
    windowExample.show()
    sys.exit(app.exec_())

basicWindow()