wxPython - Introduction
wxPython is a Python wrapper for wxWidgets (which is written in C++), a popular cross-platform GUI toolkit. Developed by Robin Dunn along with Harri Pasanen, wxPython is implemented as a Python extension module.
Just like wxWidgets, wxPython is also a free software. It can be downloaded from the official website http://wxpython.org. Binaries and source code for many operating system platforms are available for download on this site.
Principal modules in wxPython API include a core module. It consists of wxObject class, which is the base for all classes in the API. Control module contains all the widgets used in GUI application development. For example, wx.Button, wx.StaticText (analogous to a label), wx.TextCtrl (editable text control), etc.
wxPython API has GDI (Graphics Device Interface) module. It is a set of classes used for drawing on widgets. Classes like font, color, brush, etc. are a part of it. All the container window classes are defined in Windows module.
Official website of wxPython also hosts Project Phoenix – a new implementation of wxPython for Python 3.*. It focuses on improving speed, maintainability, and extensibility. The project began in 2012 and is still in beta stage.