The Zen of Python is a collection of 19 "guiding principles" for writing computer programs that influence the design of the Python programming language. Software engineer Tim Peters wrote this set of principles and posted it on the Python mailing list in 1999. Peters's list left open a 20th principle "for Guido to fill in", referring to Guido van Rossum, the original author of the Python language. The vacancy for a 20th principle has not been filled.
Peters's Zen of Python was included as entry number 20 in the language's official Python Enhancement Proposals, which was released into the public domain. It is also included as an Easter egg in the Python interpreter, which can be displayed by entering