I had an AMAZING idea for what would easily be my best blog article, ever. But I might be a bit out of touch 😅 Help me figure this out: Have you ever heard of the “P vs NP” problem? Ok, and if you have, what about “NP-completeness”? Have you heard of this term? Could you explain it back to me?

Do you folks know any meetups that would be happy to host a remote talk? I have a couple of new talk ideas that I'd love to get some feedback on!

If you only remember to do one thing today, it should be proposing a talk for #PyConUS 2026. CFP closes today! us.pycon.org/2026/speakin...

What if... I started streaming regularly (weekly?) on a quest to CONQUER Leetcode? Start from #0001, and solve all Leetcode problems? Is that something watchable or am I just being ridiculous?

Advent of Code is over (only 12 days this year) and I'm kind of sad I don't have a reason to stream today. I liked streaming! What if I wanted to stream more? What should I stream about?

Congratulations to the new #Python #SteeringCouncil! 🗳️ @pumpichank.bsky.social 🗳️ @corona10.bsky.social 🗳️ @pablogsal.com 🗳️ @savannah.dev 🗳️ @yhg1s.bsky.social discuss.python.org/t/steering-c... Welcome Savannah & thank you to @gpshead.bsky.social for your service! hugovk.github.io/python-steer...

It's so ANNOYING to break out of nested loops. Auxiliary variables, conditional statements, non-linear paths through your code... It's a mess! But if you extract the looping logic to a generator, you get: - less indentation ✨ - a flat loop you can easily break out of ✨

📢 Public service announcement: Don't buy from me: Don't buy my books. Don't sign-up for my courses. Don't attend my cohorts. Apparently, I'm a scammer. 🤷 At least, that's my interpretation of this comment from a subscriber... Should I delete them from my mailing list?

After yesterday's flop, today I'm live streaming to solve day 10 of Advent of Code and hopefully go back to day 9 part 2 to make progress on finishing it!

A visualisation of day 7 from Advent of Code. Worked on this during yesterday's stream, although the colouring was added off stream.

7 days of Advent of Code diagrams from my streams and analysis sessions!

Today was a fun Advent of Code problem! Join me at 5pm UTC (in ~2h40min) as I livestream my solution and a visualisation for today's part 2. We'll be implementing a very efficient Python solution with sets and counters! Here's the link for later: youtube.com/@mathsppblog...

Advent of Code doesn't rest during the weekend and neither do I!* In ~3 hours (@ 5pm UTC) I will be livestreaming my Python solution for day 6. We'll also go back to day 5 to implement the MOST efficient ⚡️ solution for day 5, since my solution from yesterday was kinda inefficient. 🐌

I need ideas. Later today (in ~2 hours) I'm going to be livestreaming while I solve Advent of Code day 5. I want to livestream for ~1h. But the problem won't be long enough. What should I do after, along a similar theme?

🔴 I'm going live in 30 minutes to solve Advent of Code day 4. I'm sure we'll have some time left, so we'll also work on a visualisation for day 4. Here's the link: youtube.com/@mathsppblog... See you in 30!

Anatomy of a list comprehension. Understand this and you'll never need to look up list comprehensions again.

I'm going live to solve Advent of Code, day 2, in 10 minutes! And we'll also be going back to the visualisation for yesterday's problem... The link is in my profile :)

Here's a lie developers tell themselves: “Recursion is useless” That's a coping mechanism because you're afraid of recursion... But you shouldn't be afraid! Recursion is actually nice ✨ And it's a very natural way to express certain algorithms... Let me show you an example.

This random tourist really took me by surprise: So I arrived at the train station, saw a tourist couple trying to buy tickets, and offered to help. They sorted the tickets out by themselves but wanted to double-check the platform they should be in. I tell them the right one…

Oh by the way, you can still get ALL my 8 Python books PLUS all future updates PLUS all future books for $37.5 because of the Black Friday craze. That's $166 worth of books for a pretty penny. Here's the link: 📚 mathspp.gumroad.com/l/all-books-... Enjoy the books :)

I may or may not have been muted for the first 2 minutes of the stream 🤣

My first Advent of Code live stream will start in ~1h! See you there? Advent of Code 🧑‍💻 live-stream: www.youtube.com/@mathsppblog...

With an article from yours truly 🤩

In today's session of the Algorithm Mastery Bootcamp we talked about linear recurrence relations and how to represent them as matrices. The next step? Using fast exponentiation with repeated squaring to compute terms at LIGHTNING FAST speeds ⚡️🤓

This December I'll be publicly live-streaming myself solving Advent of Code (in Python) on YouTube, but I never streamed on YouTube. Does anyone have any tips? :D Both general streaming tips and specific YT-related ones?

This post includes Python-related sales from @lernerpython.com, @mkennedy.codes, @stephengruppetta.com, @mathspp.com, and @dataschool.io. ...plus a bonus non-Python sale from @b0rk.jvns.ca because the zines are too good not to mention.

One of my favourite things to do with Python 🐍 is trying to reimplement (parts of) modules. I just have fun doing it. 🤷 And I was thinking about `itertools.pairwise` and its generalisation, `nwise`... And how you could implement `nwise` in different ways. Here's what I got:

With the Black Friday deal (BF202550 for 50% off all my books), my book Python drops, with 179 Python tips, comes out at ~4 cents per tip... That's a bit criminal 🤣 After the BF I'll have to increase the price of this book! mathspp.gumroad.com/l/python-dr...

Inspired by @samwho.dev's brilliant interactive essays, I wrote an interactive explanation of the floodfill algorithm. (Also in preparation for Advent of Code.) Give it a read and let me know what you think -> mathspp.com/blog/floodfi... I tried using PyScript for the interactive demos...

Ok, so I was writing a Python article about the floodfill algorithm. It includes some interactive demos I created with PyScript! I was still developing and testing the demos... But someone shared it online in a major Python newsletter... So, I guess the cat's out of the bag !

Here's how to NOT get a file name from a path in Python. The string method `split` has a counterpart `rsplit` that starts splitting from the end of the string. This is useful if you only want the final segment(s) of a string.

Who can guess what I'm writing about?

Do you work in Hollywood or at a publisher? If you do, I've got the perfect Python string method for you: `str.title` Changes the case of any string into title case. “star wars: the empire strikes back” becomes “Star Wars: The Empire Strikes Back”. Much more professional!

Need a temp file in Python? Maybe you need to test a function that requires a file-like object. Or maybe you need a buffer because you're processing an amount of data so large that it doesn't fit into memory... In these situations, `tempfile.TemporaryFile` can help you out.

What I share in a Python tip: You CAN use this data structure for this. Note how, from a pedagogical standpoint, this is an instructive example. What the commenters see: You HAVE to use this code EXACTLY like this and this is the ABSOLUTE BEST solution in EVERY context.

When doing Advent of Code I always end up needing a stack. When I do, I create it by inheriting from `list`. This gives me almost everything I want for free!

33 likes on BlueSky? Am I famous now?!

I published an article about “everything related to functions”. It was supposed to be a reference article... And I forgot to talk about docstrings! 🤦 What's worse is that no one event pointed that out to me! I've fixed it now: mathspp.com/blog/pydont...

You know what's a pain to implement in Python? A moving average function. Manually keeping track of all the values being considered for the window is a pain! Unless you use `collections.deque`. Its param `maxlen` makes the window automatically evict the values you don't need.

I was going through the OVERWHELMINGLY POSITIVE reviews of my book “Pydon'ts” and I always giggle when I find this 1-star review. I mean, after 200 ⭐️⭐️⭐️⭐️⭐️ reviews, this anonymous user could think for a second and realise that the issue wasn't mine/the book's... 🤡

This GitHub Action dorny/path-filters just saved me hours of work 🥵 I have a folder in a repo with cloudflare workers: workers/ workerA/** workerB/** I want to deploy workers that get changed but not the others! That's when dorny/path-filters comes in handy! ✨

Your future you will thank you for this: The keyword `assert` takes an expression to its right. If the expression evaluates to `True`, or Truthy, everything is fine. But if it doesn’t, you get an `AssertionError`. That's a pretty unhelpful/generic error... Here's the fix:

Quick! How many string methods that change the case of a string can you name? I'll give you a hint: I thought there were only 5 but I was wrong.

All Python objects have a Truthy/Falsy value. This is the value of an object when used in a Boolean context. For example, when used in the condition of an `if` statement. Most objects are Truthy, with a few exceptions. For most types, the “nothing” or “empty” value is Falsy.

It just hit me that programming is like chess. Everyone can play. But not everyone plays beautifully… It requires practice and calculated moves. Moves that look like arbitrary choices… But if you know, you’ll see how each decision builds towards a readable codebase.

Just published a new article about the new Python 3.14 module `compression`. This module offers a neat way to access the 5 compression modules we have in Python: 👉 bz2 👉 gzip 👉 lzma 👉 zlib 👉 zstd The first four were already available as standalone modules...

When building complex readable strings, consider building them out of smaller fragments. The function `oxford_comma`, shown below, demonstrates this technique. What's the point of the smaller fragments?

Python has a very well-known naming convention: Names that start with a leading underscore are “private”. This means the outside world has no business using them. E.g., attributes and methods starting with `_` in a class mean they're for that class only.

I'm really enjoying this idea I stole from Simon Willison I now have a `tools` subdomain where I host small HTML+JS tools built with LLMs that help me with whatever random things I need. E.g., I have one that pre-fills my testimonial form and generates a URL I can share easily!

The methods `strftime` and `strptime` can be used to convert dates/times into strings and vice-versa. Here's a mnemonic to help you: 👉 `strptime` has a “P” for “Parse date/time”, so string -> date 👉 `strftime` has an “F” for “Format date/time”, so date -> string