It's an old tutorial, I suspect there are now better ways to handle the graphics (with QGraphicScene, QGraphicsView, QGraphicsItem, etc) but useful for getting a handle on layouts, signals, slots, and customizing event handlers.
Here's the first, Hello World.
#!/usr/bin/env python3
# -*- coding: utf-8 -*-
'''
PyQt4 conversion of Qt Tutorial 1
last modified: 2012-01-19 jg
ref: http://doc.trolltech.com/3.3/tutorial1-01.html
'''
import sys
from PyQt4.QtGui import (QApplication, QPushButton)
def main():
app = QApplication(sys.argv)
hello = QPushButton("Hello")
hello.resize(100, 30)
#app.setMainWidget(hello) # n/a in PyQt
hello.show()
sys.exit(app.exec_())
if __name__ == '__main__':
main()