It might be also the Scheme manifesto, but in Python its so deep rooted in the community that its practically embedded in the language itself:

Python 2.6.5 (r265:79063, Oct 28 2010, 20:56:23)

[GCC 4.5.0 20100604 [gcc-4_5-branch revision 160292]] on linux2

Type "help", "copyright", "credits" or "license" for more information.

>>> import this

The Zen of Python, by Tim Peters

Beautiful is better than ugly.

Explicit is better than implicit.

Simple is better than complex.

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