Pydantic is OP, here's why

I've made a video on Pydantic already, but version 2 has since been released, so I thought I would come back to it! You can think of Pydantic as a supercharged dataclasses, with all sorts of functionality even attrs doesn't have. It's great for APIs too!
00:00 - Intro
00:44 - Installing Pydantic [1]
01:12 - Creating models [2]
04:15 - Validating inputs [3]
08:10 - Using Pydantic with an API [4-5]
17:33 - Outro
[1] docs.pydantic.dev/latest/install
[2] docs.pydantic.dev/latest/conc...
[3] docs.pydantic.dev/latest/conc...
[4] https:://www.gov.uk/bank-holidays.json
[5] docs.pydantic.dev/latest/api/...
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If you have any questions, don't hesitate to ask in the comments! I'll try and answer as soon as I can, providing someone else hasn't already done so.
#python #coding #howto

[@DuncanBooth]

The newer version of Pydantic encourages you to write validators using Annotated. For example: from pydantic import BaseModel, AfterValidator from typing import Annotated def validate_positive(value: int) -> int: assert value > 0, "must be > 0" PositiveInt = Annotated[int, AfterValidator(validate_positive)] class Order(BaseModel): id: int item_name: str quantity: PositiveInt and now you have a reusable type annotation for positive integers.

[@Carberra]

I've never much liked Annotated, just looks really messy and ugly. That looks neat though -- where in the docs did you find that? Pretty sure it's not in the Validators section.

[@VictorOliveira-lg2qg]

Even better, Pydantic already provides types like that for convenience, which uses annotations. In this case, you can import PositiveInt like this: from pydantic import PositiveInt

[@DuncanBooth]

@@Carberra I replied with the link but can't see my reply so perhaps youtube cut out the link. It's under concepts/validators, literally the first thing under the Validators heading.

[@greob]

Pydantic is very interesting, and this makes me want to try using it more. Thanks for sharing!

[@Carberra]

You're very welcome!

[@santiagohal6747]

I love this. This is brilliant.

[@ButchCassidyAndSundanceKid]

The new version of Pydantic is re-written in Rust, should be a lot faster than before.

[@Carberra]

I've seen benchmarks claiming it's about 7x as fast as V1, didn't know that was the reason though!

[@ButchCassidyAndSundanceKid]

@@Carberra Holy crap ! I thought it was fast, I didn't know it'd be that fast. I suppose the only other framework it can beat that is the gPRC and protobuf. v1 was written in Python, but v2 was written in Rust which is in the same league as C++, that probably explains about the superior performance.

[@irlshrek]

i think if people have the time they should learn Rust!

[@ButchCassidyAndSundanceKid]

@@irlshrek The question is "IF people have the time".

[@gabriellevesque2185]

​@@ButchCassidyAndSundanceKid Same League as C 😅

[@pythonwithjames]

Really nice!

[@HerozTech]

I was recently learning golang and coming back to python i missed struct but pydantic more than makes up for that Great video👍

[@HerozTech]

one more thing What color scheme are you using, it looks awesome

[@squishy-tomato]

see the video linked in the description

[@Boot3011]

Whats the plugin that autofills your variables and stuff? Thats awesome

[@danielandreasen2293]

Looks like github copilot

[@Carberra]

Almost -- it's a competitor called Codeium. I made a video on it: kzbin.info/www/bejne/h3a4d2B3mpdgmck

[@KonstantinUb]

What's the difference between Pydantic and Marshmallow? Can they be used to accomplish the same things?

[@Carberra]

I'm not sure how functionally different they are, but Marshmallow is certainly designed to used to define ORM-agnostic schemas for databases and convert to and from JSON data. I believe you can do the same with Pydantic, but I haven't used enough of Marshmallow to delve into the differences.

[@davidmurphy563]

3:33 It took you a month to release this video? Are they better when they age? ;)

[@Carberra]

Like a fine wine 🍷

[@ayehavgunne]

I like the library called apischema which lets you use dataclasses to achieve the same thing.

[@illiasukonnik9966]

Excellent video, thanks! Please use caching when playing with external APIs, be polite ))

[@basb3603]

What theme is that?

[@Carberra]

Link to setup is in the description (:

[@ruslanoid]

TIL about `kebab-case` (until now just called it dashes or hyphens)

[@gownerjones]

Isn't the whole point of it being spelled "pydantic" that you pronounce it "pie-dantic"? :D

[@Carberra]

It may well be, I actually don't know, never heard anyone else say it 😅

[@gownerjones]

@@Carberra Well I'll be pedantic and pronounce it pie-dantic just for the irony lol

[@christianlinux8283]

I thought subclass config was deprecated

[@Carberra]

Huh, so it is. Why did they not remove that in 2.0? I just went with it cos it worked so I thought it hadn't changed.

[@ChrisAdaline]

Who else had to look up what bunting is?

[@murphygreen8484]

This guy

[@Carberra]

How very unpatriotic of you! /j

[@damonguzman]

Explainer is better than code along.

[@shadmansudipto7287]

Lol. Use a non scripting language.