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Comment by kccqzy | Hacker News Reader

> Python, AFAIK, has many features, a very permissive runtime, and perhaps (not unlike C++) only some limited subset should be used at any time to ensure that the code is manageable. Unfortunately, that subset is probably different depending on who you ask, and what you aim to do.

I'll get started on the subset of Python that I personally do not wish to use in my own codebase: meta classes, descriptors, callable objects using __call__, object.__new__(cls), names trigger the name mangling rules, self.__dict__. In my opinion, all of the above features involve too much magic and hinder code comprehension.

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There's a time and a place for each of them:

* Meta classes: You're writing Pydantic or an ORM.

* Descriptors: You're writing Pydantic or an ORM.

* Callable objects: I've used these for things like making validators you initialize with their parameters in one place, then pass them around so other functions can call them. I'd probably just use closures if at all possible now.

* object.__new__: You're writing Pydantic or an ORM.

* Name mangling: I'm fine with using _foo and __bar where appropriate. Those are nice. Don't ever, ever try to de-mangle them or I'll throw a stick at you.

* self.__dict__: You're writing Pydantic or an ORM, although if you use this as shorthand for "doing things that need introspection", that's a useful skill and not deep wizardry.

Basically, you won't need those things 99.99% of the time. If you think you do, you probably don't. If you're absolutely certain you do, you might. It's still good and important to understand what they are, though. Even if you never write them yourself, at some point you're going to want to figure out why some dependency isn't working the way you expected, and you'll need to read and know what it's doing.

> Basically, you won't need those things 99.99% of the time

That's kind of my point. If you don't need a language feature 99.99% of the time perhaps it is better to cut it out from your language altogether. Well unless your language is striving to have the same reputation as C++. In Python's case here's a compromise: such features can only be used in a Python extension in C code, signifying their magic nature.

I don't need my car's airbags 99.99% of the time.

A lot of people want pydantics and orms.

I think it's fine to have those if it makes API design and better. In my mind, there's "code you should write" and there's "code only libraries should write".

I never understood why pydantic reimplemented attrs, but doing it much slower, instead of just using attrs.

You should try Go!

It should be banned by the geneva convention.

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