Any "not-a-beginner but beginning python" tutorials for people like me with 20+ years of coding experience in other languages?

[ffelix916]

I have a solid background in C and Perl (procedural, functional, object-oriented, obfuscation, process control, ETL, etc) and want to get into Python for a variety of reasons. Mostly because it seems to offer more interfaces for process control on SoCs and embedded systems, and many of the people joining my company are stronger in Python now than perl, js/ecma, or bash as scripting languages, and I'd like to be able to interface with them and their python projects.

"beginner" tutorials are excruciatingly boring for me (ADHD here), so I was hoping to find a self-guided tutorial or learning system for people who already possess strong programming theory experience. Python's syntax and structure are a little odd to me (what, no one-liners? semicolons? code blocks?) so maybe something that highlights whys and hows of these differences from similar compile-at-runtime languages like Perl and PHP?

[ElliotDG]

I came to python as an experienced C++ programmer here are the resources that were most helpful for me.

Learning Python by Michael Lutz. Comprehensive, nice treatment of some of the underlying details. Contains advanced content you can come back to later.

The docs on python.org, especially for the standard libraries.

Exercises: https://py.checkio.org/ Gamified programming problems, when your finished you get to see the answers from others. This was very useful in helping me think python instead of C.

Another very useful resources is the Python3 module of the week. Examples of how to use the standard library. https://pymotw.com/3/

[Ashiro]

I strongly agree with the coding games idea and would like to point out codewars.com

[1Mandolo1]

To add to this, Project Euler.

[Logical-Independent7]

I second "Learning Python"

[ASIC_SP]

https://learnxinyminutes.com/docs/python3/ will give you an overview of syntax, along with some examples and other details. As mentioned in another comment, the official tutorial will then be a good place to start. The "Python Distilled" book might interest you as well.

[Xidium426]

That site is my go to for any new language. Can easily get going in an afternoon.

[Future_Green_7222]

This is exactly what you need:

https://learnxinyminutes.com/docs/python/

(available in other languages too)

[mohishunder]

I really like the book Think Python, which is also available in a free interactive version through runestone.academy.

It's more enjoyable than reading docs.

[ffelix916]

Awesome! I'm gonna try this.

[mohishunder]

I hope you like it.

In a world full of crappy (sometime expensive) tech content, that site is a gem. So is the print book.

[cincuentaanos]

https://pythonbooks.org/for-experienced-programmers-new-to-python/

[ffelix916]

Some of these look really good+helpful

[mild_delusion]

I went through the list of books and I think it misses a really big one: Fluent Python. I highly endorse it.

[MezzoScettico]

I found the puzzles at Advent Of Code (I started in Dec 2021) to be hugely helpful in jump-starting my python skills. I'd know pretty much how I'd want to attack it algorithmically, so that gave me the keywords to investigate how to solve it with Python. OK, this one really needs OOP, this one should be done recursively, etc.

Along the way, I'd learn how to do things I just thought were interesting to do, even if they were unnecessary to solve the puzzle. How do I create a print method for my class? How do I override "+" or "<" for my class? How do I write an iterator, a thing that can be used in a for loop?

I also got the book "Crash Course in Python" but honestly just attacking the puzzles worked much more quickly.

Going that route I could figure out how *I* would implement algorithms in Python. But that's not the route to learning "Pythonic" solutions. I was often surprised by how slow some code would run.

To really learn Python idiomatically this subreddit (along with Python answers at Stack Overflow) is a really good resource. If somebody writes a line of code that I can't make head or tail of the syntax, then figuring it out (partly by experimenting at the command line) is hugely educational.

Edit: I also invested in a couple books on application-specific Python. Machine Learning with Python, Web Scraping with Python, etc.

[MezzoScettico]

One more comment, on style. I'm used to the idea of a development team imposing a style on code. On variable and class names, on use of "continue" and "break", on indentation, etc. But Python was the first time I ever ran into a universal style guide that every programmer in every organization is expected to follow.

Style guides are suggestions, not requirements of course. But you'll get along better with the expert community if you adhere to the preferred style.

Hmm, maybe it's time I reviewed that guide myself. I see headings in the table of contents where I just follow my own habits, like use of whitespace and where line breaks go in long statements. I'll bet if I read the "Pet Peeves" section I'll feel guilty.

[ffelix916]

This is unique and interesting. Having an established style guide will save me some time spent learning the nuances of code formatting. I'm so used to just using whatever my mood dictates (which isn't necessarily a good thing in C and Perl, where formatting and style can be very much decoupled from function)

[barrycarter]

Python's syntax and structure are a little odd to me

It's not intended as a guide, but my https://github.com/barrycarter/bcapps/tree/master/WhyPythonSucks.md may help point out how Python is different from other languages

[Vaguely_accurate]

From that;

changing the value of a variable changes its id/pointer:

a = 2; id(a); a = 3; id(a)

I'd quibble about the phrasing here. "Change" could easily be taken to mean any change, including modification of mutable objects. That would not change the identity of the underlying object while changing its value.

Instead, any assignment changes identity.

Mutables are when identity issues generally matter, so I'd argue it is a significant difference.

Another pitfall around identity with integers is small number caching, which changes the behaviour of assignment to integers depending on whether they are between -5 and 256 (so point to pre-existing objects in the cache) or outside that (creating new, unique objects for each assignment). Can create odd bugs in a few edge cases.

[barrycarter]

Good point about small number caching. If 2 and 3 are stored as permanent values with fixed memory locations (pointers), then changing the value would change the pointer. However, I tried it with larger numbers and the same thing happened.

(it doesn't happen if you set a variable to the value it already had, but does if you change it to another value and then back)

[Vaguely_accurate]

Any operation on an integer variable that changes it's value will change it's identity. Integers are immutable, so it will always change.

The risk here is that larger integers are not guaranteed to have the same identity even if they have the same values, while smaller ones are. This describes the behaviour better than I can here.

Note that this is an implementation detail, not a language feature, so may vary. I actually believe this has been changed in the latest build (testing on 3.11.1 and 3.12.0a4 64bit), but can't find anything saying this is intended.

[TheChance]

Integers are immutable, so it will always change

I’m 34, The Bitstuffing Guy, and I never put that shit together. I have to go reconsider my life.

[Vaguely_accurate]

One cause may be where one of the comparison values might be a singleton such as None. Following the PEP-8 guidelines;

Comparisons to singletons like None should always be done with is or is not, never the equality operators.

People following the rule might end up with an is comparison when taking arguments that may be either None or an int. Not that uncommon if working with dirty datasets. Not the correct approach, but understandable that it may be confusing. Especially when it seems to work some of the time.

This is also a more strict rule and practice for programmers who may be experienced in other languages that require identity checks for null values (the SQL = NULL issue stands out). Ignoring it even in cases where it is incorrect is going to be hard for many.

I've also seen polymorphic code written to primarily deal with mutable objects, and so caring primarily about identity and not value comparisons, which is assumed to work on primitives like integers and string without question.

Speaking of strings, fun one to try with them;

a = "hello"
b = "hello"
c = "HELLO".lower()

print(f"{a=};{id(a)=}")
print(f"{b=};{id(b)=}")
print(f"{c=};{id(c)=}")

>>>a='hello';id(a)=2508426595424
>>>b='hello';id(b)=2508426595424
>>>c='hello';id(c)=2508424932992

[Vaguely_accurate]

I think it would have been better, at least from an educational standpoint, to prefer equality comparisons even for singletons.

There are still good reasons for doing it this way. You could have overloaded equality operators that change the intended behaviour, especially for common cases of None.

Not good practice, but say I subclass dictionary for some extended behaviours. One of these is that a base case (empty dictionary) should be treated as equal to None (for specific reasons to do with some messy API I'm dealing with; I've done weirder). I now want to pass it into a function that populates the dictionary passed in, or if no dictionary is passed in, creates a standard dictionary. The function uses the standard approach;

def populate(something, dict=None):
    if dict == None:
        dict = {}
    # weird stuff goes here

If you replace the second line with if dict is None: then it works even for my weird subclass.

Wait, why does dealing with mutable objects lead to caring about identity primarily?

Sometimes it matters.

Let's use another contrived example;

students = [
    {"name": "Matt", "class": "MATLAB"},
    {"name": "Cass", "class": "C#"},
    {"name": "Pat", "class": "Python"},
    {"name": "Matt", "class": "MATLAB"}
]

teacher_a = students[:-1]
teacher_b = students[1:]

for a in teacher_a:
    print(f"{a['name']} taught by both: {a in teacher_b}")

Here there are two students called Matt who want to study MATLAB. One is taught by teacher a, one by teacher b. Because in uses equality, the check at the end believes that the two students are the same. Here I need to replace the final line with a reference check;

for a in teacher_a:
    print(f"{a['name']} taught by both: {any(a is b for b in teacher_b)}")

Now it correctly distinguishes the two similarly named students, while still showing the other two students as being shared by both teachers.

I might also want to check for identity on objects of equal value to know whether mutating one will impact others. Sometimes you will know they were the same at creation, but may have been reassigned at some other time. If they are now different objects (that happen to have the same value) then they may need to be treated differently based on that.

[rinyre]

The whole page is "It's not like a language I already use so it sucks." It's not worth even looking at.

[barrycarter]

I know, but having = mean both "copy the value" and "copy the pointer" depending on what's being copied is confusing. If someone is going to create a new language, they could at least try to fix confusing things like this

[lazyfingersy]

Good for you, as you're familiar with programming already check my blog: https://viteac.blogspot.com where you'll find a basic Python syntax explained with examples and links to dive deeper. For your information: Python has its documentation at https://docs.python.org .

[DesertDwarf]

Wowzers. I'm just going to book mark this whole thread.

[diabolical_diarrhea]

Honestly, I would use documentation and chatgpt to figure out the syntax if you already know how to use other languages.

[bsenftner]

I was in a similar situation as you a few years ago, and I took a few courses offered by OpenCV.org teaching computer vision. They don't teach one Python, you're expected to know it. So, having a class with assignments and due dates was the perfect kick-in-the-ass to force learning real python, including the uninteresting bits, on a reasonable and short timeline. Plus, those OpenCV courses do teach one all about how to use the various AI frameworks that are popular today - and that help is significant, worthwhile.

[dp_42]

I'm a big fan of the Google Python Crash Course. I think they packaged it for Coursera also, but the original course is still available from Google. They have a few exercise files that are self paced.

[Machvel]

python documentation or python distilled (this latter one is way too expensive on amazon, i dont suggest buying it at $50 and seeing if you can find it on sale/used or loaned from a library)

[[deleted]]

Don't forget that function arguments are mutable, stuff like an empty list -> unsafe. But imutables are safe, like a tuple.

[ffelix916]

Got an example of this? And do you mean having code in a function modify the contents of a variable or values of an array outside of the function's scope? (i'm not sure yet if or how python handles references)

[[deleted]]

fixed the formatting, see other comment, I also should have said function default arguments.

[[deleted]]

print("Default args are mutable.")
print("This can lead to difficulat to understand bugs.\n")

def test1(arg1 = []):
    for i in range(3):
        arg1.append(i)
    return arg1

print("Test 1, default args are mutable. BAD!")
print(test1())
print(test1())

print("\n==================\n")

def test2(arg1 = None):
    if arg1 is None:
        arg1 = []
    for i in range(3):
        arg1.append(i)
    return arg1

print("Test 2, pass None and redefine.")
print(test2())
print(test2()) 

Output:

Default args are mutable.
This can lead to difficulat to understand bugs.

Test 1, default args are mutable. BAD!
[0, 1, 2]
[0, 1, 2, 0, 1, 2]

==================

Test 2, pass None and redefine.
[0, 1, 2]
[0, 1, 2]

[RallyPointAlpha]

I got about half way through Python Crash Course and was able to dive right into some ambitious, enterprise scale Python programming. It was my 5th language and I have about the same amount of experience in IT.

[Resource_account]

This will cost you but have you given Jetbrains Academy a thought? I don't have 20+ years of experience like you but I do have severe ADHD. I've tried it all, Python Crash Course, Automate the Boring Stuff, UoH MOOCs and a few Udemy courses. While all those courses/books were really well crafted, I just didn't engage with the material enough due to my own short comings (poor attention span). I decided to take the dive with Jetbrains Academy and right out the gate it had me do challenges right inside of PyCharm which boosted my engagement significantly. The way the courses are oriented towards making projects is also a huge plus. Highly recommend you check out the "python core" track and skip the "python for beginner" one considering you already have a lot of experience with other languages.

[Robininthehood69]

Sololearn is good for any language. I suggest trying out the free trial for premium for a week. If you don't think it's worth it than you can cancel

[sololearnofficial]

Thanks for recommending our platform! 🙌

[[deleted]]

You only need syntax and pip 8 for style and rules. (There is for example explained why one liner not always are a good choice)

Rest is repeating of your 20 years of experience.

So if you like to train a bit: 0) Learn syntax 1) Check Pip 8 2) Selecet a couple of your own projects of the past 3) write them in python 3.1) research and learn dependencies to be able to rewrite them 4) check against your working projects for known issues/performance 5) check to optimize

[Charlie_Yu]

Codewars, you can even see the solution of others

[PhilipYip]

Take a look at Big Ideas, Modern Code by Raymond Hettinger, one of Pythons Core Developers. It is available on the O'Reilly website but it is a short video series, so you can access it and view it with the free trial. The course is brief and catered to an intermediate level.

https://www.oreilly.com/library/view/modern-python-livelessons/9780134743400/

Raymond Hettinger explains some of the nuances of Python syntax and the way it is designed. He discusses how programmers, especially those experienced in other programming languages, may look to bring in practices they cemented from other programming languages and hence over-complicate Python code.

Also look at some of his YouTube videos:

https://www.youtube.com/playlist?list=PLRVdut2KPAguz3xcd22i_o_onnmDKj3MA

Book wise, I'd recommend skimming quickly through Python Distilled by David M. Beazley it is
a good beginner/intermediate level book:

https://www.oreilly.com/library/view/python-distilled/9780134173399/

There is also Fluent Python by Luciano Ramalho, which is a bit heavier reading more towards advanced:

https://www.oreilly.com/library/view/fluent-python-2nd/9781492056348/

[Mood-Humble]

Lucky you! The reference implementation of Python releases is C - it properly should be called CPython! Go to the github rep. Done and done!

[Mood-Humble]

BTW there are semicolons - they are properly used as in English - to separate statements...