kotov_dev's profile picture. Full-stack dev & course author. 10K+ paid students. Simplifying Python concepts, learning discipline & motivation.

Sergei Kotov | Python Made Simple

@kotov_dev

Full-stack dev & course author. 10K+ paid students. Simplifying Python concepts, learning discipline & motivation.

置頂

When I learned OOP, every book used Dog, Cat, and Animal classes. I thought: "Classes must model real-world objects." Later, I saw code with classes like: › AuthenticationHandler › DataSerializer › CacheManager Eureka! Classes aren't just mirrors of reality—they're…


Need to catch both IndexError and KeyError? Just use their parent — LookupError:

kotov_dev's tweet image. Need to catch both IndexError and KeyError?
Just use their parent — LookupError:

Calculating the same value inside a loop? Please, move it outside. Calculate once. Save energy. Be eco.


Just hit 1,000 followers—doubled in 20 days! 🎉 Thank you for valuing my content and engaging.


You're procrastinating on building because you think you need more knowledge. You don't. With just the fundamentals: › Variables & types › Loops & conditionals › Lists & dicts › Functions › File I/O › Basic classes You can build: › Web scrapers (collect data) › CLI…


Sergei Kotov | Python Made Simple 已轉發

I have never understood this fascination with cheat sheets. Whenever one posts a cheat sheet of anything, you get too excited. What do you need them for? Do you stick them on your walls for reference?😅 I mean, the whole internet is a cheat sheet. I will be more fascinated…


"We don't store your password" isn't marketing hype. It's true. Companies store password hashes, not passwords. How hashing works: › One-way only (can't reverse) › Same input = same output › Different input = different output They can verify your password but can't…

kotov_dev's tweet image. "We don't store your password" isn't marketing hype. It's true.

Companies store password hashes, not passwords.

How hashing works:

› One-way only (can't reverse)
› Same input = same output
› Different input = different output

They can verify your password but can't…

A to-do app can teach you more than you think. › Simple to-do (no storage) → fundamentals › With file saving → File I/O, data formats › To-do server → FastAPI, DB, REST APIs › CLI client → Client-server architecture One simple app. Four skill levels. Countless concepts.


I write posts, reply to quizzes, and built letpy.io because I love imagining someone having that "aha!" moment. I don't see those moments happen, but I hope they do. So honestly, I'm more excited about the creation process than the teaching itself.


Can't believe it. More than 100K views! Note for my X notebook — cats work well even in programming posts. 🐱

When I learned OOP, every book used Dog, Cat, and Animal classes. I thought: "Classes must model real-world objects." Later, I saw code with classes like: › AuthenticationHandler › DataSerializer › CacheManager Eureka! Classes aren't just mirrors of reality—they're…



Catching all exceptions is like taking painkillers without seeing a doctor. The pain vanishes, but you ignore your body's warnings. › Pain signals something is wrong (e.g., sitting on a hot stove). › Exceptions indicate broken code. Silencing them hides issues until…

kotov_dev's tweet image. Catching all exceptions is like taking painkillers without seeing a doctor. The pain vanishes, but you ignore your body's warnings.

› Pain signals something is wrong (e.g., sitting on a hot stove).
› Exceptions indicate broken code.

Silencing them hides issues until…

I don't believe in "programmer brains." If you can make pasta (boil water, add pasta, wait 9 minutes, drain), you understand algorithms—a sequence of steps to achieve a goal. Programming is writing those steps in a language computers understand. Everyone starts confused.…


🎉 Giveaway Winner Announced! Congrats @fcbDavidBeloved — you've won FREE lifetime access to my updated letpy.io Python course! Check your DMs for your access link and code 🔐 Thanks to everyone who entered! Stay tuned for next week's giveaway

🎉 Weekly Python Giveaway! Win FREE lifetime access to my updated letpy.io course (€80 value)! 10K+ students completed the first version. Now it's even better. To enter: › Follow @kotov_dev › Like + Retweet › Reply "I'm in!" ⏰ Random winner from replies in…

kotov_dev's tweet image. 🎉 Weekly Python Giveaway!

Win FREE lifetime access to my updated letpy.io course (€80 value)! 10K+ students completed the first version. Now it's even better.

To enter:

› Follow @kotov_dev
› Like + Retweet
› Reply "I'm in!"

⏰ Random winner from replies in…


Just hit 800 followers! I'm grateful to everyone who follows. Hope I'm bringing something useful to your programming journey. I doubled my following (400→800) in 25 days. Here's what I changed: Before: › 1 post/day › 5-10 lazy replies/day › Took 3 months to reach 400…

kotov_dev's tweet image. Just hit 800 followers!

I'm grateful to everyone who follows. Hope I'm bringing something useful to your programming journey.

I doubled my following (400→800) in 25 days. Here's what I changed:

Before:

› 1 post/day
› 5-10 lazy replies/day
› Took 3 months to reach 400…

Async ≠ Parallelism Async is about waiting efficiently, not running simultaneously. Like a chef: while one dish is in the oven (waiting for API call), they prep the next (calculating formulas). Not two chefs. One chef, zero wasted time.


United States 趨勢

Loading...

Something went wrong.


Something went wrong.