# importing libraries
from PyQt5.QtWidgets import * 
from PyQt5 import QtCore, QtGui
from PyQt5.QtGui import * 
from PyQt5.QtCore import * 
import sys


class Window(QMainWindow):

    def __init__(self):
        super().__init__()

        # setting title
        self.setWindowTitle("Python ")

        # setting geometry
        self.setGeometry(100, 100, 650, 400)

        # calling method
        self.UiComponents()

        # showing all the widgets
        self.show()

    # method for components
    def UiComponents(self):

        # creating a QCalendarWidget object
        self.calendar = QCalendarWidget(self)

        # setting geometry to the calendar
        self.calendar.setGeometry(50, 10, 400, 250)

        # setting cursor
        self.calendar.setCursor(Qt.PointingHandCursor)


    # overriding key press event
    def keyPressEvent(self, e):

        # when escape key is pressed
        if e.key() == Qt.Key_Escape:

            # show the present date
            self.calendar.showToday()
            print("Calendar Show Today")


# create pyqt5 app
App = QApplication(sys.argv)

# create the instance of our Window
window = Window()

# start the app
sys.exit(App.exec())

Calendar Show Today
Calendar Show Today
Calendar Show Today
Calendar Show Today