No, there are several. But all of them should strive to be Pythonic, including in the sense of offering "one, and preferably only one, obvious way to do something".
>Dumb comment.
Oh, the irony.
>I was talking about architectures not syntax.
And the Zen of Python is about architecture and APIs too, not just the syntax of the language. They are generic guidelines about how to write Pythonic programs.