This seems like too much effort has been put into it for it to be a purely satirical exercise, but I really cannot see why anyone would prefer to use this within Python, rather than (say) reaching for a proper type-safe functional language and either using that directly, or calling out to it from Python code.

As a person who teaches functional programming at degree level, this is the kind of thing that would put people off FP before they even get in the door. It is obviously less ergonomic than standard Python, and the code you end up with is no safer or more abstracted than what you started with.

That said, if the authors really do think it's a better way for programming in Python, and it works for them, then more power to 'em.