Mark Summerfield, owner of Qtrac Ltd., is an independent trainer, consultant, technical editor, and writer specializing in C++, Go, Python, Qt, and PyQt. His books include Rapid GUI Programming with Python and Qt; C++ GUI Programming with Qt 4, Second Edition (with Jasmin Blanchette); Programming inPython 3, Second Edition; and Advanced Qt Programming, and Programming in Go, all from Addison-Wesley.