super/MRO, Python's most misunderstood feature.

Рет қаралды 210,058

Күн бұрын

Python's super does NOT mean "parent".
It means "next in line". What line? The Method Resolution Order (MRO) of an object, which defines the search order for attribute lookups. super() uses some very sneaky techniques, such as examining the current stack frame, and object proxying. All this is explained in great detail, for both single and multiple inheritance, and a pure Python implementation of super is given.
CONTEST CURRENTLY CLOSED! THE WINNERS HAVE BEEN CONTACTED, CHECK YOUR COMMENT TO SEE!
OFFICIAL CONTEST RULES:
1. All entries must comply with the KZfaq community guidelines ( kzfaq.infocommunity_gu...) and KZfaq Terms of Service (kzfaq.info?gl=US&t.... Entries that violate KZfaq guidelines are automatically disqualified.
2. KZfaq is not a sponsor of the contest and viewers are required to release KZfaq from any liability related to the contest.
3. Privacy notice: no personal data will be collected for this contest.
4. In order to enter, you must (a) be one of my subscribers, AND (b) make a top-level comment to the video including #pycharm or #clion somewhere in the comment.
5. The contest is free, there is no fee required to enter.
6. Winners will be chosen randomly 1 week after the date the video went live from all users who have entered and not been disqualified.
7. Each winner will be notified via a comment reply from me that details what prize was won (e.g. "Congratulations! You have won XYZ. Please email me."). I will ask the winner to contact me by email, and I will reply through email with a random token which must be posted as another reply to the winning comment from the winning account in order to verify account ownership and prevent fraud.
8. Each winner will have 72 hours to respond AND prove account ownership or their prize is automatically forfeited and another winner will be chosen.
9. A winner can only win 1 prize per contest.
10. The prize pool for this contest is: 4 licenses for PyCharm Professional and 5 licenses for CLion ("Free 1-Year Personal Subscription"), which are products made by JetBrains. A prize consists of 1 license, which will be delivered in the form of a redeemable code that can be redeemed at www.jetbrains.com/store/redeem/ before May 01, 2022.
11. You may not enter the contest if doing so would be a violation of any relevant federal, state, and local laws, rules, and regulations, including U.S. sanctions.
― mCoding with James Murphy (mcoding.io)
Source code: github.com/mCodingLLC/VideosS...
super docs: docs.python.org/3.8/library/f...
A super guide: rhettinger.wordpress.com/2011...
SUPPORT ME ⭐
---------------------------------------------------
Patreon: / mcoding
Paypal: www.paypal.com/donate/?hosted...
Other donations: mcoding.io/donate
Top patrons and donors: Jameson, Laura M, Dragos C, Vahnekie, John Martin, Casey G
BE ACTIVE IN MY COMMUNITY 😄
---------------------------------------------------
Discord: / discord
Github: github.com/mCodingLLC/
Reddit: / mcoding
Facebook: / james.mcoding
CHAPTERS
---------------------------------------------------
0:00 Intro
0:32 Basic super usage
2:34 super does NOT call your parent
4:29 Method Resolution Order (MRO)
6:18 super means "next in line"
6:48 How MRO is determined
8:07 How to design with super
12:01 How does Python super work?
16:53 Two-argument super
18:01 One-argument super
18:18 Implementing super in Python

Пікірлер: 905

@MrBughyman1000 2 жыл бұрын

Isn't the search that the MRO is doing the breadth-first search?

@mCoding 2 жыл бұрын

In this case it was the same as a BFS, but in general it does not have to be! See the L(Z) example in en.wikipedia.org/wiki/C3_linearization for a case where it is not a BFS.

@Erotemic 2 жыл бұрын

@@mCoding my assumptions keep breaking and I love it.

@logicweaver7152 Жыл бұрын

Technically, it does a depth-first, left-right search and can contain duplicates. Then, it removes all but one of the duplicates. The last duplicate is preserved, all else are removed. Eg: class A: pass class B(A): pass class C(A): pass class D(B, C): pass so depth-first, left-right search list for 'D' would be something like this: ['D', 'B', 'A', 'object', 'C', 'A', 'object'] Now, all earlier duplicates will be removed for the __mro__, i.e the first 'A', and the first 'object' will be removed from list. ['D', 'B', 'A'(first 'A', hence removed), 'object'(first 'object', hence removed), 'C', 'A', 'object'] the final list is this: ['D', 'B', 'C', 'A', 'object']

@play005517 3 ай бұрын

@@mCodingthat algorithm looks like an O(n^3) mess lol

@AtriumComplex 2 жыл бұрын

I've been programming in Python professionally for almost 10 years and I learned something in this video.

@mCoding 2 жыл бұрын

Glad to hear!

@davidyoung623 9 ай бұрын

Same!

@TemporaryForstudy 27 күн бұрын

does that mean these things are not going to be used in industry?

@Ratimus_ 22 күн бұрын

@@TemporaryForstudy not if you want to keep working in that industry ;-)

@TemporaryForstudy 21 күн бұрын

@@Ratimus_ Thanks for the information. Are you a python developer?

@nou9225 2 жыл бұрын

i spent days treading in convoluted documentation to finally understand MRO, multiple inheritance, and super (had to also get through descriptors to understand the bounding mechanics)... and here it is, a 20 minute video that explains everything. this channel is way too underrated.

@Lodinn 2 жыл бұрын

Raymond Hettinger's old talk "Super is considered super" is fairly good, too

@mCoding 2 жыл бұрын

Thanks for the kind words! And I also recommend "Super is considered super"! It's linked and Hettinger was (I believe) the one who coined the "next in line" phrase.

@Lodinn 2 жыл бұрын

@@mCoding If anything, it's worth watching for the volunteer part (explaining cooperative inheritance and MRO) at very least. Visuals like that make things a lot easier to comprehend/memorize. I'm not a fan of some of Raymond's teaching techniques but this specific part was brilliant.

@theplanebrain Жыл бұрын

With that experience maybe you could make the documentation better? I’m not trying to be one of the “then open a pull request!” guys but it sounds like you have special insight that might help future users.

@Mutual_Information 2 жыл бұрын

The *level* of this channel is 👌. I've been coding in Python for quite awhile and I always learn stuff here. It's really refreshing when a lot of what is out there is like "how to use dicts in Python!"

@dimitriosdesmos4699 2 жыл бұрын

yeah that the problem, he is teaching super , to advanced people.

@QuantumHistorian 2 жыл бұрын

So true, it's high level, but it doesn't use an overwhelming amount of jargon. Learning a new programming language is a pain, because 90% of the material and tutorials are "This is the syntax for a for loop", while the remaining 10% is an argument on stack exchange about the best boosting the efficiency of a highly specific package from 1994 with some compiler meta-optimization. It's either teaching a complete beginner how to code for the first time, or a set of code-words that will remind an expert of how to do something. When I almost always want is help on turning my ok-ish code, into good code. I wish he did material on, say, C# or Julia, so I could go from a basic understanding of the surface feature of the language to having an idea of how the structure of it works.

@__lasevix_ Жыл бұрын

Exactly! And it's always some of the most error-prone structures that you can't understand!

@pacificll8762 7 ай бұрын

Love your videos!

@QuantumHistorian 2 жыл бұрын

This is why multiple inheritance, especially "diamond" multiple inheritance is evil. Even if you're one of the 0.01% who knows how it works, it will still trip you up when you dont expect it (that is, 99% of the time). Having recently come across C#'s solution to this (a class can only inherit from 1 class, but can inherit from as many Interfaces as it wants), I now think python's approach is too liberal. Of course that's the whole python ethos, but sometimes it creates far more traps than necessary. #pycharm

@mCoding 2 жыл бұрын

Too many people take my job security comment a bit too seriously!

@loicgrossetete9570 2 жыл бұрын

Here the trap isn't that problematic imo, once you inherit from multiple classes there is an obvious problem with super. Best practise I think is to specify which parent function you want to call

@Ormaaj 2 жыл бұрын

So you've discovered interfaces. My favorite C# feature. Initially they seem hard but once you get the hang of it you'll never go back to MI. When you get a bit deeper you'll hit covariance / contravariance with interfaces, and the slightly ugly type parameter constraints that all kind of tie together. C#'s type system is not quite perfection.

@ativjoshi1049 2 жыл бұрын

That's precisely the case with Java as well.

@bradleykreider3358 2 жыл бұрын

Don't all classes derive from object, making any multiple inheritance diamond shaped?

@JamesxBond007 10 ай бұрын

James: your expert knowledge of not just Python, but C, and CPython implementation - along with dense and info-rich presentation - make for a quite rare resource of deep, under-the-hood understanding of Python. Thanks for putting in the work!

@biffenb7534 2 жыл бұрын

Thanks for being so clean and straight-to-the-point in how you present your topics. Your videos are quite like 3Blue1Brown but for programming. Keep up the dry humor, stellar stuff. #pycharm

@lepsycho3691 2 жыл бұрын

Amazing insights into the super() function implementation in Python! Thank you for your great work, I always learn something new!

@mCoding 2 жыл бұрын

Glad it was helpful!

@Buoy2 2 жыл бұрын

The only time I used multiple inheritance it was a big mistake, it became impossible to have the classes cooperate nicely. A slightly more verbose solution based on composition solved the same problem without all the subtle bugs #pycharm

@mCoding 2 жыл бұрын

As is always a question you should ask, just because you *can* solve the problem with multiple inheritance, *should* you?

@renatocustodio1000 2 жыл бұрын

@@mCoding I believe 99,99999% of the time the ansewer is sounding NO.

@drygordspellweaver8761 2 жыл бұрын

Rule 2 of OOP: Favor Object composition over inheritance

@academyonnet Жыл бұрын

@@mCoding Could you please make a video where you show with a few different examples to replace a solution with inheritance with functional composition?

@JohnHollowell 2 жыл бұрын

The 2 argument super used to be the required way of calling super in python2. So glad we don't need that anymore

@mCoding 2 жыл бұрын

May Python 2 rest in peace, forever!

@d00dEEE 2 жыл бұрын

Very nice! Your example code at the end is the part that was missing in PEP 3135 back when it was written, it would have cleared up how super works for most people. For a good example, look at PEP 343 - with Statement, where the "Specification" section shows exactly how it works in a very clear fashion.

@MsSuyash1995 2 жыл бұрын

Even though I am aware about using super and cooperative multiple inheritance when I watched the iconic talk of Mr. Raymond Hettinger on super()... But even then, my mind was simply in awe when you dived into the details... I never even imagined that super class is sort of implementing a Proxy pattern...

@sirmidor 2 жыл бұрын

A good addition for cooperative inheritance is that the root class' sink method verifies that both *args and **kwargs are empty at that point and throws an error if either isn't. This helps prevent unnecessary arguments being passed somewhere in the chain that stick around after changes/refactoring as the *args and **kwargs in the signatures of children mean that static code analysis often won't see anything wrong.

@guilhermecaltabiano9565 2 жыл бұрын

If someone says that python is easy, sure they didn't saw this video, it's a good example of how much python has to offer below the surface. Very helpful! Thanks!

@sebastianandrade8500 2 жыл бұрын

This comment applies to the metaclasses one too. That one blew my mind the first time

@linlin110 Жыл бұрын

@@sebastianandrade8500 Let's not forget descriptors and __getattribute__(). Python really does a good job in hiding complexity. It's so simple yet so expressive.

@Starwort 2 жыл бұрын

IIRC, you can rebind super to have the compiler magic keep working while also allowing you to change its behaviour (it's definitely the case that using super bound to another name causes the compiler magic to fail) EDIT: To be clear, if you had written `class super:` instead of `class Super:` it would be a drop-in replacement

@michaelraphael2710 2 жыл бұрын

I find it quite enlightening when you dive deeper into how these features work rather than working with the superficial layer of when to use/ how to use these features. I always come away with some useful knowledge I can apply to my code. #pycharm

@dmsalomon 2 жыл бұрын

I love these metaprogramming videos. The best way to explain a complex language features is to show the implementation.

@UnFallenRain20 2 жыл бұрын

Another great video, the first half was satisfyingly confirming some practices I have picked up by using python for a while, and the latter half was part mind-boggling, part "oh please don't do that". Learned a lot as always, thank you James! #pycharm

@mCoding 2 жыл бұрын

Glad you enjoyed it!

@unpythonic 2 жыл бұрын

Fantastic introduction to super() and MRO, thanks.

@mCoding 2 жыл бұрын

My pleasure! Have a super day!

@dane2565 2 жыл бұрын

I love the level of depth you manage to go into in such a short time. Few guys on KZfaq deliver this stuff as well as you do. Also #pycharm :)

@sushilsharma1621 7 ай бұрын

Thanks for the video. quick question, could you share how did you remove your background from video and set computer screen as the background? which video recording software / tools you have used for making this video ? thanks,

@user-xp1jl2ot6y 2 жыл бұрын

13:18 little mistake. __getattr__ is called whenever getting attribute is failed, __getattribute__ is called everytime you trying to get an attribute.

@user-zo1me3pn4g Жыл бұрын

In current example it is the right form of using dunder getattr method. Since you don't want to get the attribute of an instance of this class but the self.obj, that will make the code work excatly as it should. Changing dunder getattr to getattribute will cause the RecusrionError because it will invoke itself infenetily long, as you're trying to get the attribute not of self.obj but of self - an instance of current class.

@jonatannystrom5432 2 жыл бұрын

I would love to see an explanation of the Walrus (:=) operator. How it works,tips and tricks, and use case scenarios. Mostly I've missunderstood when i should/can use it. My code often feels non-reable when using it. Loved this video (and ofc your previous ones)! #pycharm

@NicolasChanCSY 2 жыл бұрын

I remember that I watched Raymond Hettinger's "Super considered super!", understood a little more about the MRO but could not understand how `super()` works. Now I have watched this video and I have learnt something new today! Thank you! I still don't fully understand the `super(...)` with argument(s) form, but I guess/hope I don't need it since I don't need to consider my job security. 😂

@grawss Жыл бұрын

Love the 1-letter variables in your functions. Right after coming from one of your "nooby habits" videos too.

@10e999 2 жыл бұрын

Intermediate programming channel are so rare. It's always a pleasure watching your videos ! #clion

@naxaes7889 2 жыл бұрын

It's a bit scary how much work at runtime goes behind a simple attribute/method lookup.

@berylliosis5250 2 жыл бұрын

To be fair, it's python, which is about convenience over speed. If you want method and property lookups to be fast, you should probably be using a different kind of language

@naxaes7889 2 жыл бұрын

@@berylliosis5250 Considering that attribute/method lookups are one of the most common things you do in a programming language, it's quite frightening that what takes one machine instruction in a compiled language takes upwards of 100 *bytecode* instructions, including both branches and memory fetches. I hope (and think, but am too lazy now to check) that Python does some optimizations here to bypass this cost because I've never really felt that Python is that slow in comparison. I do expect a certain level of speed from any language.

@talshafir10 2 жыл бұрын

I looked for this A LOT through last week You’re a mind reader and your content is amazing! Thank you so much for helping the community to understand these concepts better! #pycharm

@JustMastermind 2 жыл бұрын

Your videos are always very informative and straight to the point, unlike other tutorials, where every character of code is analyzed on it's own. Keep up with these good videos #pycharm

@littleal14 2 жыл бұрын

Wanted to get into open source dev. One of the main projects I wanted to get into is pretty #clion oriented would love a key!

@devonlee5815 2 жыл бұрын

And here I thought “How complicated can super() really be?” It’s a joy to learn from you. Keep up the great content! #pycharm

@MrSteini124 2 жыл бұрын

Amazing. Your videos are so consistently great. Good work!

@bereck7735 2 жыл бұрын

Finally, a video that covers the inner details of super and how it works, also the pure python implementation of super is awesome, learnt a lot from this video, thank you so much Murphy. #pycharm

@mCoding 2 жыл бұрын

Very welcome and glad you enjoyed!

@embeddor3023 2 жыл бұрын

As a C/C++ dev, all this runtime stuff python is doing just to do basic static things is horrifying.

@josephlyons3393 2 жыл бұрын

As a Rust dev, all this unsafe UB in C/C++ is horrifying! :D

@embeddor3023 2 жыл бұрын

@@josephlyons3393 At least we don't have a whiny compiler. :) Just kidding, I like the rust's approach. Cppckeck for cpp is sometimes all what you need tho.

@josephlyons3393 2 жыл бұрын

@@embeddor3023Rustc certainly is soul crushing, lol. C++ was my main language for many years, but I mostly dev in either Rust or Python these days, depending on the task.

@karenbaghdasaryan7558 2 жыл бұрын

This channel is pure gem!

@isaacmoore3639 Жыл бұрын

This was the most I have learned about python in any 20 min ever. Subscribed

@electrocuted5010 2 жыл бұрын

Object oriented programming in Python is complicated. Thank you for this video!

@xN811x 2 жыл бұрын

Well, tbh. in most cases it's not a big deal because you can compose functions pretty easily by explicitly calling them. You don't need "object oriented" programming (more like inheritance) in these situations.

@bloodgain 2 жыл бұрын

It seems like it, but it's actually far less complicated _in practice_ than in many other languages, like C++ (public vs private inheritance, recursive inheritance [CRTP], pure abstract classes, constness concerns, public/protected/private members, etc. -- and that's before we add templating!). In both cases, though, you should really avoid inheritance for code reuse, anyway. Inheritance should be used for polymorphism. Only in some rare cases when following certain design patterns (or idioms) should you inherit anything but the interface, and in those cases, you should just follow the pattern. Generic programming is usually closer to what you want with code reuse; Python has this with duck typing, while languages like C++ do this with templates, and some others like Java fake it (somewhat poorly) with type erasure.

@trag1czny 2 жыл бұрын

Discord gang 🤙🤙

@mCoding 2 жыл бұрын

Always appreciated!

@rob011 Жыл бұрын

This was incredible. Thank you!

@lisnter 10 ай бұрын

Wow - that was complicated but enlightening. Your videos are great!

@isbestlizard 2 жыл бұрын

Note to self: never use inheritance in Python if I want my code to run fast. Seeing what goes on behind the scenes is amazing, and a bit scary... the VM must be doing *so* much work every time a super() gets called XD

@cat-.- 2 жыл бұрын

after like 8 years of programming I've come to the conclusion to use inheritance as little as possible it just creates a mess in places you never think of

@NVidea-yz1fg 2 жыл бұрын

It is impressive, how Python implements all these functionality _with Python_ - from a technological point of view. Python, as an interpreter language, implements itself by using Python... fascinating! But from the perspective of a user of the language ... all this black magic everywhere ... meh. :/ In other languages, using "clever coding" is regarded as something bad ...

@dmsalomon 2 жыл бұрын

I'm assuming that super is implemented in C (at least for cpython) and not in pure python since it's a built-in. But it could be implemented in python, aside from the class injection hack.

@sadhlife 2 жыл бұрын

Compared to most other languages, python has very little black magic. Other languages also have things like implicit `this` variable, which feels more like black magic to me

@thomaskolar90 2 жыл бұрын

I think this is a case of "practicality beats purity" :D I remember programming in Python 2, which didn't have this black magic. This meant that every. single. super call needed to be the two-argument form... Believe me, it gets old very quickly, apart from being error-prone, as you now have to mention the class you're in everywhere.

@Mihirdamncool Жыл бұрын

Loved it! Really really nice and descriptive video. Thanks for making this @mCoding. You are the best in class!!! Salute!

@vorpal22 Жыл бұрын

I love both PyCharm and CLion (the only editor I can not only stand for C++ but that I actually enjoy). I seldom use super in my projects (personal and work), but this was a good explanation.

@AlvaroALorite 2 жыл бұрын

Oh my God thank you. Having a video this concise and clear is really really helpful.

@danielguerra5970 Жыл бұрын

Hi James, I just started to seeing your videos, and they are of great quality. I'm a Mathematician and Data Scientist from Mexico. I just wanted to ask how did you achieve that deep knowledge of Python? Is there a set of subjects or books that you recommend? I have studied some basic OOP in Java. Thanks

@jaribwetshi6977 2 жыл бұрын

I am glad I came across your channel. Just realised I've been more focused on the 'how' things work in python but didn't give much thought to the 'why'...good job mate. #pycharm

@aikimark1955 2 жыл бұрын

Wow. You put in a LOT of detective work on this. Thanks.

@user-fn2vo9lh5z 4 ай бұрын

Awesome explanation, especially the part on how super works underneath the hood!! Thanks a lot.

@jonathan3488 2 жыл бұрын

Hi, great video, you always do such in-depth research! Could you perhaps do a video on creating python bindings for C/C++? It can be rather useful but I have barely seen anyone discuss it seriously and thoroughly on youtube.

@DanielLavedoniodeLima_DLL 2 жыл бұрын

Had to deal with a MRO nightmare I was building Custom Operators for an Apache Airflow application. Custom Operators basically inherit from other default Operators (to build custom solutions for your specific use-case), which in turn can inherit other operators and extra classes and so on until it gets to the BaseOperator class. To make matters worse, I wanted to merge 2 Operators into one. Took me a long time to figure out what super() was actually calling and made me have to dig into a lot of stuff to find out. Your video is really straightforward and had it been released 1 year ago would have saved a couple of days of frustration. Awesome content as always! #pycharm

@drygordspellweaver8761 2 жыл бұрын

Can you explain why you needed custom operators as opposed to just Methods?

@DanielLavedoniodeLima_DLL 2 жыл бұрын

@@drygordspellweaver8761 I needed a simple way for the Data Analysts and Data Scientists to have their own self-serving Airflow instance. Since they already knew how to use an Operator, I built that way so I could "hide the wiring" behind that complicated process behind an interface in which was more familiar to them.

@mtomazza 2 жыл бұрын

good Lord, so much depth inall of your videos. Keep up the great work

@cexploreful 2 жыл бұрын

Finally i understooood! Great explanation!!!

@igk1288 2 жыл бұрын

Always excited to see new videos from this channel! I appreciate seeing how things work behind the scenes. Thanks for the awesome content. #clion

@mcdolla7965 Жыл бұрын

absolute knowledge.... , though most of these i knew olredy, but you are actually going gr8 sir. how to get which class is being run by super , i did not know...thanks for that and really appreciable work sir, all hands down.

@jecaballeror 2 жыл бұрын

I started using super() due to the structure of a project (needed a parent class with some general methods and configs, and child classes made to inherit from it). I was exposed to it from a previous video from you, where you used to create a subclass dictionary to be able to call the subclass given the parameters ( this is something i ended up needing in said project). I already knew some of the stuff you expose here due to researching, but as always, you go the extra mile. Thanks for your content. #pycharm

@mCoding 2 жыл бұрын

Very welcome and glad to hear you're doing your own experiments! That's the best way to learn it!

@pablovirus Жыл бұрын

Best videos on youtube dude, thank you so much

@jurjenbos228 Жыл бұрын

I've been asked many times about a clear explanation of super(), and here it is!

@cisimon7 2 жыл бұрын

After so many years using python, I still learn a lot from this channel. #Pycharm #CLion

@jbramley 2 жыл бұрын

I really enjoy your deep dives into the nitty gritty details of python. I always come out feeling smarter. #pycharm

@piotrmazgaj Жыл бұрын

Your python knowledge is truly frightening... I like the video, but man this is a deep serious stuff. I'm overwhelmed.

@joostvisser8537 2 жыл бұрын

An excellent explanation as always! Personally I'm still a newbie when it comes to Python, I'm currently learning how to use classes in general, and this is the first time I'm hearing about class inheritance. Yet I could still follow a lot of the explanation, which says a lot about how good you are as a teacher! Thank you :) #pycharm

@reaperfs2371 2 жыл бұрын

Always getting a deeper understanding about Python through your videos. Thank you for making such fantastic and no nonsense content! Also #pycharm

@gekkenhuis4863 2 жыл бұрын

I have been wondering whether a function like this exists for a long time. Thank you!

@mCoding 2 жыл бұрын

Very welcome!

@peterkita6391 2 жыл бұрын

thanks for clearing this out! Was confused about super until now #pycharm

@captdev 2 жыл бұрын

Thankyou!!! I have never had super explained to me but have seen it everywhere and even used it a fair bit #pycharm

@danieldistefano2000 2 жыл бұрын

Great video. This was one of those I was really waiting for. Just a question. So this all means that I can't correctly inherit from multiple parents, if those parents where not specifically built to be siblings, right?

@rx97_mc 2 жыл бұрын

Oh this is perfect, i was just struggling with this like an hour ago. I had some dataclass inheritance structure (frozen) and i had some classmethod as a factory which i wanted to inherit but it all fell apart.

@BoringTimesSharingInfo 2 жыл бұрын

The way the topics are choosen and presented is astonishing 🔥😇 #pycharm

@sirbastidas9491 10 ай бұрын

Muchas gracias, enserió necesitaba mucho entender esto, y esta clase me ha ayudado bastante! translate: Thank you very much, I really needed to understand this, and this class has helped me a lot!.

@vaibhavpimple7507 Жыл бұрын

Thannks, You make difficult topics interesting and easy to learn

@yaroslavdon 2 жыл бұрын

Great video as always. You explained well the inner mechanics of the super() method. To understand super() perfectly, one must watch both Reymond's video and yours. About the optional arguments: I used once super() inside a list comprehension. It took me quite a while to understand why Python threw an error each time. Apparently, list comprehensions (or generator expressions) are considered to be their own scope, and thus do not apply super() correctly. The remedy was to apply super() with two arguments; worked like a charm. #pycharm

@mistral___ 2 жыл бұрын

It's always interesting to see in-depth explanations of how a language works under the hood, like this or the ",=" python operator you explained in a past video. Keep up the quality content :) #pycharm

@mCoding 2 жыл бұрын

That's an old one! You must be a long time viewer! Or a dedicated one at least!

@tandavme 2 жыл бұрын

Thank you, great video!

@Fahadahammed 2 жыл бұрын

Thanks for the content...

@jitushukla7889 2 жыл бұрын

Awesome explaination. I'm revising Python after so long and these type of videos helps us to get a deeper knowledge of certain aspect of the code. #pycharm

@franklydoodle350 2 жыл бұрын

Wow. Amazing explanation.

@oddlyfriendly Жыл бұрын

Interesting and insightful as usual. What's really surprised me the part where you unraveled the mystery behind how zero argument super works, which also explains the older form of super. Thanks for your content! #clion

@Ozy_Viking 2 жыл бұрын

This was a bit over my head but so interesting and helpful. I love learning Python, and thank you for your videos. #pycharm

@luissaybe 4 ай бұрын

Great video this concept, thanks

@zaringers 3 ай бұрын

It’s so interesting thank you!

@vnikolayev 2 жыл бұрын

Always wanted too see info about super but never thought about it directly. Thanks! #pycharm

@sawcondeez 2 жыл бұрын

I finally understood why multiple inheritance is dangerous. I didn't understood it in University. Thanks!

@hankertric 2 жыл бұрын

Awesome advanced Python stuff. Already knew about how super works and the MRO but didn’t know about the implementation details. #pycharm

@crnpowerimmortal 2 жыл бұрын

I am using this frequently but this is far the best explanation . #pycharm

@Simon-fu8sd 2 жыл бұрын

I just hope to be as insightful as this guy one day

@yudhiesh1997 2 жыл бұрын

I was just reading reading an article from Real Python about super() to clear some doubts and you posted a video about the same thing! #pycharm

@PanduPoluan Жыл бұрын

This video again shows how Python's compiler does magic things. And again emphasizes how it's very important to understand when things happen (in the compiler or in the interpreter).

@tooru 2 жыл бұрын

Love your videos! Every single one is so helpful and on topic. You are the first channel on the list that I recommend to my friends. #PyCharm

@gabrielbelouze7765 2 жыл бұрын

Side effect of this video: seeing a weird / operator in the __init__ of your custom Super implementation, looking it up and learning about positional only arguments. Loved this video!

@mohsenhassani495 2 жыл бұрын

What a flexibility from python that allows you to change MRO, I even saw someone in SO that changes MRO in runtime I'm curious if other languages provide that kind of flexibility or not

@ashduino101 2 жыл бұрын

Great tutorial! I've always wondered what super() did, especially with the syntax differences between 2.7 and 3, but this tutorial did a great job of explaining that! #clion

@mCoding 2 жыл бұрын

Great to hear! Also you get a CLion license! Contact me by email!

@TechSY730 Жыл бұрын

Personally, for those very few times it _appears_ ambiguous which defining class the `super` will go to, I either use the super call with arguments, or just outright call `superclass_name.function_name(self)` explicitly. That way I don't have to require the reader to untangle the MRO algorithm. The downside of course is that now the super classes have to be named multiple places. The class's definition and any place I need to use this trick. But I consider that worth not requiring knowledge of the "deep magics" of Python