To this book’s first editor, the late Frank Willison, for the early years.

To this book’s later editors, for tolerating my nondeterministic schedule: Laura Lewin on the second edition, Jonathan Gennick on the third edition, and Mary O’Brien at the end.

To the people who took part in a technical review of an early draft of this edition: Fredrik Lundh, Valentino Volonghi, Anna Ravenscroft, and Kyle VanderBeek.

To Python creator Guido van Rossum, for making this stuff fun again.

To Tim O’Reilly and the staff of O’Reilly, both for producing this book and for supporting open source software in general.

To the Python community at large, for quality, simplicity, diligence, and humor.

To C++, for frustrating me enough to compel me toward Python; I think I’d rather flip burgers than go back :-).

To the thousands of students of the 170 Python classes I have taught so far, for your feedback on Python in general, and its applications. You taught me how to teach.

To the scores of readers who took the time to send me comments about the first two editions of this book. Your opinions helped shape this book’s evolution.