try_pyqt5.py

#!/usr/bin/python3

import sys
from PyQt5.QtWidgets import QApplication, QMainWindow, QLabel
from PyQt5.QtGui import QPainter, QPen
from PyQt5.QtCore import QTimer, Qt

class MainWindow(QMainWindow):
  # constructor
    def __init__(self):
        QMainWindow.__init__(self)
        # counter
        self.i = 0
        self.width = 500
        self.height = 500
        self.setGeometry(0, 0, self.width, self.height)
        # make QTimer
        self.qTimer = QTimer()
        # set interval to 1 s
        self.qTimer.setInterval(1000) # 1000 ms = 1 s
        # connect timeout signal to signal handler
        self.qTimer.timeout.connect(self.updateCount)
        # start timer
        self.qTimer.start()

    def updateCount(self):
        self.i += 1
        self.update()

    def paintEvent(self, event):
        painter = QPainter(self)
        painter.setPen(QPen(Qt.green,  8, Qt.DashLine))
        for i in range(self.i):
            painter.drawEllipse(40 + i * 50, 40, 400, 400)

qApp = QApplication(sys.argv)
# setup GUI
qWin = MainWindow()
qWin.show()
# run application
sys.exit(qApp.exec_())