This is PyQt5 tutorial. The tutorial is suited for beginners and intermediate programmers. After reading this tutorial, you will be able to program non trivial PyQt5 applications.
Table of contents
A unique e-book covering advanced features of the PyQt4 library: Advanced PyQt4 tutorial.
Qt5 tutorial covers the Qt5 library in its native C++ language. PyQt4 tutorial covers the earlier version of the PyQt library. To refresh your knowledge of the Python language there is a Python tutorial on ZetCode. wxPython tutorial, PyGTK tutorial, and Tkinter tutorial are tutorials for other popular Python GUI bindings.