Do We Still Need Dataclasses? // PYDANTIC Tutorial

  Рет қаралды 195,959

ArjanCodes

ArjanCodes

Күн бұрын

Pydantic is a very useful package that makes dealing with data much easier, similar to what Python's built-in dataclasses do. Where Pydantic shines is in dealing with validating and sanitizing data. In this tutorial video, I show you how it works, and when to choose Pydantic over dataclasses in your code projects.
The code that I worked on in this video is available here: github.com/ArjanCodes/2021-py....
💡 Here's my FREE 7-step guide to help you consistently design great software: arjancodes.com/designguide.
🎓 Courses:
The Software Designer Mindset: www.arjancodes.com/mindset
The Software Designer Mindset Team Packages: www.arjancodes.com/sas
The Software Architect Mindset: Pre-register now! www.arjancodes.com/architect
Next Level Python: Become a Python Expert: www.arjancodes.com/next-level...
The 30-Day Design Challenge: www.arjancodes.com/30ddc
🛒 GEAR & RECOMMENDED BOOKS: kit.co/arjancodes.
A few interesting links to articles and books:
- Design Patterns: Elements of Reusable Object-Oriented Software by Erich Gamma, Richard Helm, Ralph Johnson, and John Vlissides: amzn.to/3jllgyH
- Principles of Package Design: Creating Reusable Software Components by Matthias Noback: amzn.to/2NETK3l
- Clean Code: A Handbook of Agile Software Craftsmanship by Robert Martin: amzn.to/3qVZgNs
- The original Design Principles and Design Patterns article by Robert Martin: fi.ort.edu.uy/innovaportal/fi...
👍 If you enjoyed this content, give this video a like. If you want to watch more of my upcoming videos, consider subscribing to my channel!
💬 Join my Discord server here: discord.arjan.codes
🐦Twitter: / arjancodes
🌍LinkedIn: / arjancodes
🕵Facebook: / arjancodes
👀 Channel code reviewer board:
- 0xUnicorn
- Ryan Laursen
- Sybren A. Stüvel
🔖 Chapters:
0:00 Intro
0:52 Explaining the example
1:54 Creating a Pydantic Basemodel
4:42 Adding field validation
9:47 Adding model-level validation
12:54 More possibilities by adding a Config class
14:03 Converting the model instances to a dictionary
14:38 Other things that Pydantic can do
15:38 So, are dataclasses obsolete?
#arjancodes #softwaredesign #python
DISCLAIMER - The links in this description might be affiliate links. If you purchase a product or service through one of those links, I may receive a small commission. There is no additional charge to you. Thanks for supporting my channel so I can continue to provide you with free content each week!

Пікірлер: 231
@anuruddhabandara3540
@anuruddhabandara3540 2 жыл бұрын
In KZfaq there are lot of python contents. But 99% are for beginners. You are the only guy who teach python advance concepts very clearly. You are doing a such a amazing job sir. Keep it up. Good Luck! 🙌
@ArjanCodes
@ArjanCodes 2 жыл бұрын
Thank you - glad you like the videos!
@jakobullmann7586
@jakobullmann7586 Жыл бұрын
Check out mCoding
@theultimatereductionist7592
@theultimatereductionist7592 Жыл бұрын
How you feel about Python KZfaq videos is EXACTLY how I feel about all MATH videos. I specialize in differential algebra. There exist literally ZERO videos about differential Galois theory, for example! Or differential rings. I know less about Python now in January 2023 than 8 years ago when I began studying it. In fact, I know less about programming now than I did in Summer 1981 when I took my first computer coding class: Fortran at local community college.
@theultimatereductionist7592
@theultimatereductionist7592 Жыл бұрын
Yes, there SHOULD be MANY more ADVANCED TOPIC videos for non-beginners. However, 99% of all Python creators/coders are beginners. Extreme beginners. That is why 99% of the videos are for beginners.
@broccoloodle
@broccoloodle Жыл бұрын
You gave him at least one new subscription for your comment
@Newascap
@Newascap 3 жыл бұрын
I was just looking up fast api, with tortoise and this. You are literally reading my brain like an open book. Thanks for uploading as always.
@ArjanCodes
@ArjanCodes 3 жыл бұрын
Thank you, glad to be service again ;)
@raccoonteachesyou
@raccoonteachesyou 3 жыл бұрын
Thank you very much for choosing topics that are not only for beginners but for more advanced users. This kind of topics are really enjoyable.
@ArjanCodes
@ArjanCodes 3 жыл бұрын
Thank you very much!
@mei2654
@mei2654 2 жыл бұрын
In my opinion Pydantic serves a very specific purpose, which is parsing and validating data. If you know what data you are working with and are sure what type of data you have, there is just no reason to use pydantic as the instance creation time is higher for a pydantic model compared to a dataclass
@ALIENdrifter66
@ALIENdrifter66 Жыл бұрын
Well, that's not really an opinion, data validation is something you must do when you can't trust the input data. If you 100% know that it's well formed and conforming data validation is redundant and thus, not efficient. That's exactly why you have booth option with Python dataclasses and Pydantic dataclasses, they're not substitutes but complements
@Luca1993x
@Luca1993x 2 жыл бұрын
After watching and rewatching your content for just 2 weeks I can already let you know that you have made me a better Software -Engineer. Your creative work matters to many! Thank you a lot!
@ArjanCodes
@ArjanCodes 2 жыл бұрын
Great to hear! I'm happy that the videos are helpful to you.
@atahirince
@atahirince 2 жыл бұрын
me need to learn automatic doc creation :D and be better developer
@tmmrtn
@tmmrtn 3 жыл бұрын
3:21 Python 3.9 deprecated typing.List in favor of built-in type list (or dict, set. tuple, etc), which is much nicer because you don't need to import anything. (Additionally, there were many other deprecations from the typing module in favor of their collections.abc counterparts, so make sure to check that out too). Really these days, I only go to typing for "type theory" kind of stuff, like Any and Optional. Great video nonetheless! I'm a big user of attrs, which fills a a similar, but different, void, and didn't really know how they compared until I watched this video. Thanks!
@ArjanCodes
@ArjanCodes 3 жыл бұрын
Thank Tim! I learn something new every day, thanks for pointing that out. I’ll look at it and switch over to the built-in types in my videos.
@Kevin-jm1go
@Kevin-jm1go Жыл бұрын
True that you dont need to import anything, but with typing.List you can also specify whats inside the list.
@tmmrtn
@tmmrtn Жыл бұрын
@@Kevin-jm1go That also works with the built-ins. For example, `foo: list[str] = ['hi', 'there']` works as you'd expect. Try it out!
@JGnLAU8OAWF6
@JGnLAU8OAWF6 Жыл бұрын
And now Optional[something] can be replaced with something | None
@_DRMR_
@_DRMR_ Жыл бұрын
if you want your code to run on multiple version of python it's still useful to use the import
@NoxMar9Personal
@NoxMar9Personal 2 жыл бұрын
Great video. Things to note about the difference vs dataclasses. By doing runtime (i.e. on every object of your class creation and every change to validated field) you are taking quite a considerable performance hit. So don't use pydantic on classes you don't need to. If your data comes from the outside (user input, file, HTTP request and so on) you should absolutely validate it but don't do that for data-focused class. Also pydantic offers a module called `pydantic.dataclasses` that lets you use dataclasses with validation. Note that BaseModel provides another functionality as well but if you don't need it and want some validation for your datalcasses you can use this with minial changes to your dataclass-using code.
@luizhenriquelongo1485
@luizhenriquelongo1485 3 жыл бұрын
Oh Man, I'm from Brazil and for a long time I've been looking for this kind of content. With this whole technology bubble I've just seen superficial content about technology "how to create a crud in Django" and it has its own value but when you decide to go deep into the technology that you use most part of time we needed to get a book and try to extract as much as possible from it, but now we have you buddy, it's so nice to hear this deep content about python and it's like you've said "if you want to become a better software developer" you should probably go with arjan codes hahaha. Thank you for your content.
@ArjanCodes
@ArjanCodes 3 жыл бұрын
Thank you so much! I’m happy you’re enjoying the videos and that they help you. Ultimately, having a proper background in software design principles and patterns, knowing them through and through is one of the most important skills to have as a software developer. And that’s why I’m doing these kinds of videos instead of highly specific recipes. Feel free to spread the word to anyone who you think might be interested in this as well!
@amitkumarSaveSoil
@amitkumarSaveSoil 2 жыл бұрын
I really needed your videos to get on next level no other channel covers what your channel covers. thankyou so much
@pinakadhara7650
@pinakadhara7650 2 жыл бұрын
One of my favourite things with Pydantic is that it supports nested objects i.e an object as an attribute for another object. Really helpfull when dealing with related objects.
@LucasNaruto8107
@LucasNaruto8107 3 жыл бұрын
Just fell in love with pydantic. I was poking around the code and noticed that pydantic solves the problem for nested dataclasses, for this matter I modified the title and subtitle to support mult lang (each field was now a list of text and lang pair), i created an extra class called MultLangStr and modified the json, pydantic identified the nested information and used the proper class whilst built-in dataclass ignored it and keept the dict format.
@ArjanCodes
@ArjanCodes 3 жыл бұрын
Awesome!
@CharanThakur655
@CharanThakur655 3 жыл бұрын
videos are getting better and better. Thanks a lot for your time and effort, much appreciated.
@ArjanCodes
@ArjanCodes 3 жыл бұрын
Thank you so much!
@silkogelman
@silkogelman Жыл бұрын
Thank you so much for this very interesting Pydantic example with both validation levels Arjan! 🙏😀 I'm hoping you'll blend in more Pydantic in your tutorials in the future. FYI: for the price field you can use Decimal or condecimal with max_digits and decimal_places to more accurately represent money.
@Sycord
@Sycord 2 жыл бұрын
Really helpful video! Even just finding out dataclass is the better fit for my project and seeing some good clean code is always a chance to learn. I really like that you put emphasis on the small things of nice code like adding docstrings. Do you have a video on what class methods are?
@rafael_tg
@rafael_tg 2 жыл бұрын
Looking at this guy coding makes me feel noob in python again
@zarakolagar7068
@zarakolagar7068 3 жыл бұрын
wow, i was just searching for a tutorial on pydantic. As a newbie, i can say that your videos have single handedly upgraded my knowledge of the field. thank you very much and please keep up the good work 😊
@ArjanCodes
@ArjanCodes 3 жыл бұрын
Thank you Zara! I’m happy that the videos are helpful!
@Julien-hg8jh
@Julien-hg8jh 2 жыл бұрын
your content is so good, i learn a lot and it made me better. Thank you a lot!
@sukanyar4373
@sukanyar4373 Жыл бұрын
Excellent tutorial on pydantic ! :) Thank you! :) 🙌
@maxwell2201
@maxwell2201 2 жыл бұрын
Really awesome video, I feel like I'm learning a lot about best practices really quickly watching these.
@ArjanCodes
@ArjanCodes 2 жыл бұрын
Glad you enjoyed it!
@ArjanCodes
@ArjanCodes 3 жыл бұрын
Also check out my original dataclasses video if you haven't seen that yet: kzfaq.info/get/bejne/rLiGidydntvFipc.html.
@stifferdoroskevich1809
@stifferdoroskevich1809 3 жыл бұрын
Wow! Beautiful coding... And Pydantic, very powerful! love that dict(exclude/include feature), remembers me a NoSql DB style query.
@ArjanCodes
@ArjanCodes 3 жыл бұрын
Thank you - glad you liked it!
@cosmicblack
@cosmicblack Жыл бұрын
As always, excellent video thanks for the time, i learned something now to implement it
@cosmic_Robot
@cosmic_Robot Жыл бұрын
Great video Arjan. Subscribed.
@ArjanCodes
@ArjanCodes Жыл бұрын
Thank you, glad you enjoyed the video!
@evyli7322
@evyli7322 2 жыл бұрын
Great introduction. I didn't know about Pydantic before but now introduced this in one of my own open source projects. You have a new subscriber. ❤️
@ArjanCodes
@ArjanCodes 2 жыл бұрын
Welcome onboard ;).
@olegpopov3180
@olegpopov3180 2 жыл бұрын
Thank you for the clear explanation!
@ArjanCodes
@ArjanCodes 2 жыл бұрын
Glad it was helpful!
@user-hk3ej4hk7m
@user-hk3ej4hk7m 2 жыл бұрын
This looks really nice, I'm interested in seeing how it will integrate with typing.Annotated coming with python 3.10
@pahvalrehljkov
@pahvalrehljkov Жыл бұрын
My go to for anything related finishing project. Even as hobby programmer i almost always use your tutorials to make proper code, and in end i remove my bugs from code.
@ArjanCodes
@ArjanCodes Жыл бұрын
Glad to hear they’re helpful!
@dr.mikeybee
@dr.mikeybee 2 жыл бұрын
Thanks! Good stuff.
@ipelezikis
@ipelezikis Жыл бұрын
Very interesting stuff. Continue the great work!!
@ArjanCodes
@ArjanCodes Жыл бұрын
Thank you!
@ahmedtremo
@ahmedtremo 2 жыл бұрын
Best Pydantic tutorial on the youtube
@robertbrummayer4908
@robertbrummayer4908 2 жыл бұрын
Great video and interesting topic.
@kevinz1991
@kevinz1991 2 жыл бұрын
so helpful and clear thank you so much!
@ArjanCodes
@ArjanCodes 2 жыл бұрын
Glad it was helpful, Kevin!
@i701Dev
@i701Dev 2 жыл бұрын
Subscribed. Thanks for the video!
@ArjanCodes
@ArjanCodes 2 жыл бұрын
You’re welcome. And welcome onboard 😉
@charlesmeruwoma5409
@charlesmeruwoma5409 2 жыл бұрын
@ArjanCodes, You are a maestro!
@ArjanCodes
@ArjanCodes 2 жыл бұрын
Thank you so much!
@konstantinosmaravegias4198
@konstantinosmaravegias4198 8 ай бұрын
I want to thank you from my bottom of my heart! You have made me a better Data professional!
@ArjanCodes
@ArjanCodes 8 ай бұрын
I'm glad my content has been helpful! :)
@ylazerson
@ylazerson Жыл бұрын
great video - thanks!
@ArjanCodes
@ArjanCodes Жыл бұрын
You bet!
@vikas416
@vikas416 2 жыл бұрын
Thanks Arjan for awesome video on pydantic and its uses. I was wondering if we need to add '@classmethod' after validator and root_validator while defining a class, as according to documentation both validator and root_validator are classmethods themselves.
@HandcartRule46
@HandcartRule46 Жыл бұрын
Excellent tutorial. More of these please, thank you! :-)
@ArjanCodes
@ArjanCodes Жыл бұрын
Thank you , will do!
@alvin_paul
@alvin_paul Жыл бұрын
You are one of the best if not the best Python Channels that I know of. I am learning a lot from you 😊 Keep up the interesting topics and good work 👍👍👍
@ArjanCodes
@ArjanCodes Жыл бұрын
Thanks, will do!
@FullStackWithLawrence
@FullStackWithLawrence 6 ай бұрын
this is helpful, thanks for sharing.
@ArjanCodes
@ArjanCodes 6 ай бұрын
Glad you enjoyed the content, Lawrence!
@Kinnoshachi
@Kinnoshachi 3 жыл бұрын
You are a treasure in innumerable universes
@ArjanCodes
@ArjanCodes 3 жыл бұрын
Thank you - you’re so kind!
@AustrianAnalyst
@AustrianAnalyst 3 жыл бұрын
Just found your channel. Awesome stuff :)
@ArjanCodes
@ArjanCodes 3 жыл бұрын
Thanks man!
@brahimboughanam1662
@brahimboughanam1662 Жыл бұрын
oh thank you arjan
@machinimaaquinix3178
@machinimaaquinix3178 Жыл бұрын
Great tutorial, you earned a new sub.
@ArjanCodes
@ArjanCodes Жыл бұрын
Thanks Machinima, happy you’re enjoying the content! and Thanks for subscribing!!
@ChrisHalden007
@ChrisHalden007 2 жыл бұрын
Great video!!!
@ArjanCodes
@ArjanCodes 2 жыл бұрын
Glad you liked it, Chris!
@michaellohier
@michaellohier 2 жыл бұрын
Hi Arjan, great video. I often watch your content and I love it. I have a simple question though: does your ISBN10FormatError really need its “value” attribute?
@ArjanCodes
@ArjanCodes 2 жыл бұрын
Thanks, Michael! It can be useful sometimes to have extra information in an Error object that you can do something with. For example, if you want to parse the value and then do something else with it to respond to the error.
@sharifahmed1925
@sharifahmed1925 2 жыл бұрын
Hi Arian Love your videos 👍🏽 I wanted to ask if you have any videos explaining how and when to use the __init__ function and the super() function as well as the **kwargs? I’ve seen you use them in your videos Are these explained in your course on your website?
@slaweksx1564
@slaweksx1564 Жыл бұрын
Very useful and interesting. Than you Arjan. Small correction to custom exception, there should be inheritance from ValueError. Otherwise FastAPI generates status 500 without Pedantic validation message.
@abraham_o
@abraham_o 28 күн бұрын
Dataclasses wouldn't ignore any additional attribute in the dataset used to initialize an instance of the class, it will always raise an Exception, another beautiful thing about pydantic, pydantic will just ignore any extras. Which comes in very handy when using them to model third-party response for syntax highlighting rather then just relying on dictionaries.
@srdjan780
@srdjan780 2 жыл бұрын
Good video! TBH pandas could have been used here as well. As someone who often works with immutable data, what I would love to see from you would be an OOP vs FP in python and when to use which, as thats a question that gets raised often :)
@ArjanCodes
@ArjanCodes 2 жыл бұрын
Great suggestion, thank you!
@songokussj4cz
@songokussj4cz 2 жыл бұрын
Very nice, I didn't know about that. Is it good for filtering data too? For example: return all books that have title starting with xxx (but without for-cycle, more like JSONPath?
@neilmurphy7064
@neilmurphy7064 2 жыл бұрын
Was just randomly poking around... Trying to get smart, Eating popcorn when oh bam, this exactly solves today's problem! Thanks!
@ArjanCodes
@ArjanCodes 2 жыл бұрын
You're most welcome :).
@AndrewMelnychuk0seen
@AndrewMelnychuk0seen 2 жыл бұрын
Awesome stuff.
@ArjanCodes
@ArjanCodes 2 жыл бұрын
Glad you enjoyed it
@user-gp9zb9gs1u
@user-gp9zb9gs1u 2 жыл бұрын
Great video! Thanks for video and link of your Git repository !
@ArjanCodes
@ArjanCodes 2 жыл бұрын
Glad it was helpful!
@user-gp9zb9gs1u
@user-gp9zb9gs1u 2 жыл бұрын
I’m glade that my tutor recommended your channel to me wish you a good luck and more video)
@jval7
@jval7 2 жыл бұрын
amazing!
@ArjanCodes
@ArjanCodes 2 жыл бұрын
Thank you - glad you liked it!
@balajiveerasingam3602
@balajiveerasingam3602 2 жыл бұрын
Thanks for the explanation, it helps me a lot . what is weighted sum? why we are subtracting 10 - index ?
@adamlasry1691
@adamlasry1691 2 жыл бұрын
Thank you
@brunosompreee
@brunosompreee 2 жыл бұрын
Thanks!
@ArjanCodes
@ArjanCodes 2 жыл бұрын
Thanks and glad you liked the video!
11 ай бұрын
@ArjanCodes I'd love to see an updated version using the new Pydantic v2, your thoughts on it, and how it sits now in the pydanticV2 vs dataclasses p3.11 vs attrs
@wuzixiao1
@wuzixiao1 10 күн бұрын
Another great video. I thought pedantic is just for validation but I know more now. It is great tool to deal with json object like book = [(**list) for list in json]
@ArjanCodes
@ArjanCodes 13 сағат бұрын
Glad it was helpful!
@AnyaSheven
@AnyaSheven 2 жыл бұрын
this video just kinda changed my life))
@ArjanCodes
@ArjanCodes 2 жыл бұрын
Hopefully in a good way 😊
@SeamusHarper1234
@SeamusHarper1234 2 жыл бұрын
The text in the background
@stoic1987
@stoic1987 2 жыл бұрын
would you be able to reveal your setup (hardware etc. mouse keyboard) for your work as well?
@BaronXOfficial
@BaronXOfficial 2 жыл бұрын
Can we just take a moment to appreciate Arjan's typing skills? I'm impressed haha great work on the video as always!
@jassam246
@jassam246 2 жыл бұрын
the video speed is increased while typing, you can see it whith the head mouvements
@TheWolverine1984
@TheWolverine1984 2 жыл бұрын
Thank you! I learn some useful stuff from this. Can you define a custom parser for one of the fields? For example if your data is a list of songs with that have a title datafield that is actually both artist and song title separated by ' = '. For example "Metalica - Nothing Else Matters'. Can you define a custom parser that splits this into two separate fields in your model?
@ArjanCodes
@ArjanCodes 2 жыл бұрын
I think the root_validation method returns the value to be set in the object, so you can modify the value that you receive there - haven’t tried it though.
@TheWolverine1984
@TheWolverine1984 2 жыл бұрын
@@ArjanCodes Thanks for the tip!!
@theultimatereductionist7592
@theultimatereductionist7592 Жыл бұрын
There exist many MANY ideas I would love to code, but I know they are not worth it: no matter in what language I code them. They are all math ideas. A lot (not all) are coding the solutions to PDEs and ODEs. Some are for papers I wish to publish. Python is the only language I know, and just barely. Used to know C++, a little Java, and Fortran. I realize now that the mathematical ideas are simply too complex to be coded. For example in 2020 I attempted to code computing all infinitely many solutions for a trinomial w=C*z-z^A where w, C, A are complex numbers. Got close, but there was no way to get roots, z, that are within error limits when plugged back into the trinomial. Had hoped to publish it. But I had to leave it unfinished. Definitely a HUGE lesson about NOT coding anything deep or complicated: OTHER than the simplest of calculations, say, with a for loop. In other words, Python is my extension of a handheld calculator.
@SeamusHarper1234
@SeamusHarper1234 2 жыл бұрын
At this point, I don't care about the topics of your videos anymore. I just watch it for all the best practice and explanaition while programming.
@ArjanCodes
@ArjanCodes 2 жыл бұрын
Glad to hear you like the videos!
@glibmar
@glibmar 2 жыл бұрын
Hi @ArjabCodes, Thank you for your videos. They are very helpful. Once problem which I'm trying to solve. During the running pydantic model a lot of validation happen. Do you know the way how we can display/print/report these validations? I understand that if data is not valid we will get the error, but I want to see what was validated during the run time. Do you know how to do this?
@anindyasundarmanna6683
@anindyasundarmanna6683 2 жыл бұрын
At 11:15, is writing the condition like this better? if not ("isbn_10" in values or "isbn_13" in values): Btw Love your content. I was thinking of pydantic when watching your dataclasses video, and then found this. I used pydantic in FastAPI and it's absolutely awesome!
@RatafakRatafak
@RatafakRatafak 2 жыл бұрын
Hi, can you please tell us which VSCode color scheme you are using? Thanks!
@climbit9555
@climbit9555 2 жыл бұрын
One little advantage of pydantic is that mutable default arguments are easier to use. I know dataclasses have the field possibility, but that has its limits and is a little ugly. Also the validation implementation is a lot nicer in the newer versions :)
@mohamedtarek8899
@mohamedtarek8899 2 жыл бұрын
it's really better for parsing like you what you have done, However if this data is internally, i mean inside my application, i will lose a lot of resources within dynamic checking, although i might use attr class or dataclass for that task... thanks for sharing your ideas with us...
@saketkr
@saketkr 16 күн бұрын
I know pydantics better now, thanks. :-)
@ArjanCodes
@ArjanCodes 15 күн бұрын
Glad to hear the video was helpful!
@Mike-ol4ng
@Mike-ol4ng 2 жыл бұрын
what is the cls in the isbn_10_valid function?
@sekus
@sekus 3 жыл бұрын
Can you post the link for your code that you stated in this video on Github? I can't seem it in the description. Thank you!
@ArjanCodes
@ArjanCodes 2 жыл бұрын
I somehow forgot to add that. I put the link in the description.
@naderbazyari2
@naderbazyari2 Жыл бұрын
Thanks a million Arjan for great video. I had a newbie question. When I changed the order of "@classmethod" and "@pydantic.validator("isbn_10")" the way you suggested(minute 9 video), I did not get the Error. I know the importance of placing decorators in order but I do not understand how come the validation does not take place if I put the "@pydantic.validator("isbn_10")" immediately above the method declaration? it gets overridden?
@paracha3
@paracha3 2 жыл бұрын
When you are typing or coding can you please zoom in because most of us watch your videos on the phone screens. Love your content. Thanks
@ArjanCodes
@ArjanCodes 2 жыл бұрын
Thanks! In my more recent videos, I've zoomed in more on the code!
@josephlyons3393
@josephlyons3393 2 жыл бұрын
Hey Arjan, quick tip. If you are in Python 3.9+, you no longer have to import the List to do type hints with lists.... so in your example, you can just do list[book], and kill the List import.
@josephlyons3393
@josephlyons3393 2 жыл бұрын
I guess I don't know if Pydantic provides support for this or not yet...
@josephlyons3393
@josephlyons3393 2 жыл бұрын
Also, really getting into your videos. Super well done.
@ArjanCodes
@ArjanCodes 2 жыл бұрын
Thanks Joseph! Yeah, I noticed that too. Same for dict actually, so I'll stick to those from now on.
@bryancole1886
@bryancole1886 2 жыл бұрын
It kinda annoys me that after about 15 years of writing declarative class with python Traits package (and more recently using the Atom package) offering validation, notification and visualisation, people are talking about data classes as if they are new and exciting (but only offer validation?). Pydantic still only offers a few of the features in Traits.
@astronemir
@astronemir 2 жыл бұрын
Interesting 🤔
@vitoanania6042
@vitoanania6042 2 жыл бұрын
can you set an order for the objects in pydantic as for dataclasses?
@sillytechy
@sillytechy 3 жыл бұрын
Can you do a video on Type hinting in python.
@ArjanCodes
@ArjanCodes 3 жыл бұрын
Great idea, thank you.
@charlesking4291
@charlesking4291 2 жыл бұрын
When defining the root_validator check (10:00 - 13:00) why do you go to the trouble of adding the "title" field to "check_isbn10_or_isbn13" when it doesn't appear in the output message/error (12:59) ?? Seems like this was a minor bug glossed over ? I think it would be helpful to know which record was incorrect, as referenced by the title field ? Was that the intention ??
@layerabstraction2321
@layerabstraction2321 2 жыл бұрын
excuse me , I have a many-to-many sqlalchemy models but how can I create nested ones in Pydantic in order to implement crud?
@nickhodgskin
@nickhodgskin 3 жыл бұрын
In the custom exception class for "ISBN not provided", what's the benefit of doing self.title = title? It seems awesome for debugging but I didn't see it in the traceback Also, awesome video!! I consider myself a bit of a python noob, so I'm always learning new stuff from your videos 😍. Just started a small project using MVC architecture and working with classes. It's been awesome to implement some stuff that I've seen here
@ArjanCodes
@ArjanCodes 3 жыл бұрын
Thank you Nick! At the moment, that title field is indeed not doing much, but I do think this is really useful, because it allows you to pass better information in the Exception, which you can then later use for debugging, or taking other actions in you application depending on those values. You could add a repr method to the Exception class to print a better message, or it might be possible to turn the ISBN exception into a dataclass, which adds that automatically.
@mr7clay
@mr7clay 2 жыл бұрын
@@ArjanCodes Is it considered bad form to store a reference to the object in the Exception?
@ruizdani3016
@ruizdani3016 Жыл бұрын
hi, into the documentation where explain about how pydantic type more than 2 dates like return example () -> int, str .....
@_Szakal
@_Szakal 2 жыл бұрын
can this be used in dataclasses for validation as well?
@jesnajames2151
@jesnajames2151 2 жыл бұрын
Is it possible to use validator to check if either isbn_10 or isbn_13 is provided? Since we check two fields, is root_validator necessary?
2 жыл бұрын
As a class method it looks like the validator has access to only the single attribute value. Or did you mean combining the two attributes into one?
@71sephiroth
@71sephiroth 2 жыл бұрын
Dear Arjan, I'm a Python developer and I found this channel by accident. I see it has a ton of high quality gems, but my problem is that I don't know 'how to ArjanCodes channel' . :'D
@aruniyer1833
@aruniyer1833 3 жыл бұрын
Is there any course available for purchase
@ArjanCodes
@ArjanCodes 3 жыл бұрын
Thanks for asking. Not yet, but I am working on something.
@abteyeb7969
@abteyeb7969 2 жыл бұрын
i dont understood This but u are able in coding thinks
@brett3103
@brett3103 2 жыл бұрын
at 9:30, where does the value go?
@italobuitron1165
@italobuitron1165 Жыл бұрын
We need a Guide with Pydantic and ABC or Protocol
@typinowly
@typinowly 2 жыл бұрын
Why not simply define an array of validation methods for a dataclass (und treat dataclass like simple c-structs, without additional methods). This way all our components are neatly separated and we don't need to overpopulate our "Book" data type with a million methods. This also would make modification simpler, because then we simply add or remove validation callbacks as needed and have no need to modify the Book class. This, imho, would be way more SOLID (and thus maintainable), than what was presented in this video.
@rozarioagro5532
@rozarioagro5532 2 жыл бұрын
or use a separate library, such as cerberus. You will then get a clean, fast code and separation of concerns. I don’t understand all this hype about pydantic. You get hard to extend classes bloated with unnecessary methods that do everything but nothing of good quality.
@benjaminacar4001
@benjaminacar4001 Жыл бұрын
Thanks to Yann LeCun's little brother for sharing this knowledge.
@tranthanhbao9978
@tranthanhbao9978 2 жыл бұрын
Please make a video compare Pydantic vs marshmallow
@AndreNitschke
@AndreNitschke Жыл бұрын
When not write a Rest API, why not using attrs instead of pydantic? Is faster and not so resource hungry.
@yunes7305
@yunes7305 2 жыл бұрын
I guess it is much easier with R in dealing with json format; otherwise it is a professional tutorial thank you
@Yupppi
@Yupppi 2 жыл бұрын
2 months ago: If you're not using python data classes yet, you should 3 weeks ago: Do we still need data classes?
@ArjanCodes
@ArjanCodes 2 жыл бұрын
The answer to the second question was yes ;).
@valk9819
@valk9819 Жыл бұрын
Will we see Pydantic vs Marshmallow?
@krishnapraveen777
@krishnapraveen777 Жыл бұрын
Bro what is your keyboard? It's so soothng to hear and type i guess?
@ArjanCodes
@ArjanCodes Жыл бұрын
Keychron K3 :)
@krishnapraveen777
@krishnapraveen777 Жыл бұрын
@@ArjanCodes cherry mx silver? or red?
7 Python Code Smells: Olfactory Offenses To Avoid At All Costs
22:10
How To Easily Do Asynchronous Programming With Asyncio In Python
23:09
Khóa ly biệt
01:00
Đào Nguyễn Ánh - Hữu Hưng
Рет қаралды 19 МЛН
ТАМАЕВ vs ВЕНГАЛБИ. Самая Быстрая BMW M5 vs CLS 63
1:15:39
Асхаб Тамаев
Рет қаралды 4,6 МЛН
2000000❤️⚽️#shorts #thankyou
00:20
あしざるFC
Рет қаралды 16 МЛН
This Is Why Python Data Classes Are Awesome
22:19
ArjanCodes
Рет қаралды 792 М.
Dependency INVERSION vs Dependency INJECTION in Python
17:51
ArjanCodes
Рет қаралды 154 М.
Pydantic is the Python Package I Wish I'd Learned Earlier
11:21
John Watson Rooney
Рет қаралды 53 М.
Pydantic Tutorial • Solving Python's Biggest Problem
11:07
pixegami
Рет қаралды 242 М.
PLEASE Use These 5 Python Decorators
20:12
Tech With Tim
Рет қаралды 96 М.
This INCREDIBLE trick will speed up your data processes.
12:54
Rob Mulla
Рет қаралды 257 М.
Python dataclasses will save you HOURS, also featuring attrs
8:50
Khóa ly biệt
01:00
Đào Nguyễn Ánh - Hữu Hưng
Рет қаралды 19 МЛН