QDateEdit has a problem of display 2017-10-15

import sys
from PyQt5 import QtCore, QtGui, QtWidgets
def TestQDateEditBug():
 app = QtWidgets.QApplication(sys.argv)
 w = QtWidgets.QWidget()
 w.resize(250, 150)
 w.setWindowTitle('TestQDateEditBug')
 e = QtWidgets.QDateEdit(w)
 e.setDisplayFormat("yyyy-MM-dd")
 e.setCalendarPopup(True)
 e.setGeometry(10, 10, 150, 25)
 w.show()
 app.exec_()
 
if __name__ == "__main__":
 TestQDateEditBug()