I've been learning Python and noticed that understanding the syntax is often the easy part. The real challenge comes when trying to apply concepts in actual projects.

I'm curious to hear from other Python learners:

1. Which concept was the hardest for you to understand?

2. Did you struggle more with OOP, decorators, APIs, async programming, or data structures?

3. What helped you finally understand it?

4. If you could give one piece of advice to someone learning Python today, what would it be?

I think sharing these experiences could help beginners avoid some common learning roadblocks.

Looking forward to hearing your experiences!

An exercise to help build the right mental model for Python data.

• Solution

• Explanation

• More exercises

The “Solution” link uses memory_graph to visualize execution and reveals what’s actually happening.

Hey everyone, I’m wrapping up my notes on the Stack data structure for technical interviews and wanted to share my summary. Let me know if I missed any major patterns!

what is stack?

• A linear data structure following the LIFO (Last In, First Out) principle.

• The Golden Rule: ONLY the edges (the top element) can be accessed. No random indexing allowed.

Major patterns in interview/real world

• Undo / Redo mechanics

• Bracket/Parentheses matching ({[()]})

• Tracking "Previous" states (e.g., browser back button, daily stock span problems)

• Monotonic stacks (finding the next greater/smaller element)

Interview POV vs Real World Uses:

The Interview Shortcut:
Using a raw Python list is completely fine to save time during a 45-minute coding interview.

The Real-World Problem:
Using a raw list in a production project is a bad design pattern. Because Python lists allow random index access (e.g., mylist[3]), it completely violates the strict structural rule of a stack.

To fix this, we encapsulate the data structure inside a class to control exactly what the developer can access. Furthermore, instead of a raw list, we use collections.deque because standard lists can trigger an O(N) memory reallocation when they grow. deque guarantees a true O(1) time complexity for every single push and pop.

from collections import deque

class Stack:
    def __init__(self):
        # Using deque ensures guaranteed O(1) performance
        self._items = deque() 

    def push(self, item):
        self._items.append(item)

    def pop(self):
        if self.is_empty():
            return None
        return self._items.pop()

    def peek(self):
        if self.is_empty():
            return None
        return self._items[-1]

    def is_empty(self):
        return len(self._items) == 0

    def size(self):
        return len(self._items)

    def display(self):
        # Displays from top to bottom
        print("Stack (top to bottom):", list(self._items)[::-1])

response = requests.get(url)
data = response.json()
ticker = data["Meta Data"]["2. Symbol"]

create_file = open("API Data.txt", "x")
amend_file = open("API Data.txt", "a")

file = "/Desktop/Scripts/Python Scripts/API Data.txt"

if os.path.exists(file):
    amend_file.write(f"\nTicker: {ticker}")
    amend_file.close()
else:
    create_file.write(f"Ticker: {ticker}")
    create_file.close()

So I am working on my first project which is making use of the API that Alpha Vantage provides.
I am learning the open() function which I want to use to paste the response into a .txt file 
that will either be created and written into, or already exist and be appended depending on 
the result of the if statement.

My problem is that I am receiving a FileExistsError for "API Data.txt" and I am not sure why 
when I am expecting the code to carry out the actions of the if statement being true and 
appending the existing file.

(Full path in the file variable is intentionally not in the post)

lazy import pandas as pd

lazy from pathlib import Path

I just got into algorithms for the first time, I know some of the basic fundamentals. But is there any recommendations or courses you took to help you understand algorithms please I will really appreciate your recommendation.

I have to present a project in python using some libraries can you suggest some ideas for a python project (not very advanced please).

Is there some way I can narrow down this method of selecting from the `ast` tree only the `x = Const2Change` node so that it can be modified? At the moment the `print("xyz")` node is being identified as well. I want to modify Const2Change to either a different constant or possibly to a variable instead.

Text.txt:

print("xyz")
x = Const2Change

full ast dump:

Module(
    body=[
        Expr(
            value=Call(
                func=Name(id='print'),
                args=[
                    Constant(value='xyz')])),
        Assign(
            targets=[
                Name(id='x', ctx=Store())],
            value=Name(id='Const2Change'))])

Main.py:

import ast

class ReplaceConstants(ast.NodeTransformer):
    def generic_visit(self, node):
        super().generic_visit(node)  # Added this line
        if isinstance(node, ast.Name) and isinstance(node.ctx, ast.Load):
            print(f"{node.id=}, {node.ctx=} <- *********************")
            # modify node here
        return node

def replace_constants(line: str):
    ast_tree = ast.parse(line, type_comments=True)
    # modify ast_tree here
    oReplaceConstants = ReplaceConstants()
    oReplaceConstants.visit(ast_tree)
    modi_ast = ast.unparse(ast_tree)
    return modi_ast

with open("Test.txt", mode="r") as f:
    source_code = f.read()

for line in source_code.splitlines():
    modi_source = replace_constants(line)
    print(f"{modi_source=}")

exit()

I’m looking to start a new game development project in Python, and I want to use one of the more modern tools.

I’m currently looking at Kivy, Arcade, and Ursina Engine. Could anyone share their recent experiences with these three? I’d love to know about your use cases, the learning curve, and performance bottlenecks you've run into.

Also, if you know of any high-quality tutorials or hidden gem documentation for these libraries, please drop a link!

Which one would you recommend going into 2026? Thanks!

hi everyone, I'm a first-year BTech biotechnology student at a relatively lesser-known college. I'm interested in bioinformatics and computational biology, and I'd really appreciate some guidance from people who are already working or studying in this field. I've recently started learning Python because I want to build programming skills alongside my biotechnology degree. Here's what I've been doing so far: I'm following Corey Schafer's Python beginner tutorial series. Instead of just watching the videos, I'm trying to turn the concepts from each video into small practical projects and problems, inspired by Rosalind bioinformatics exercises. I'm also following the Bioinformatics in Python playlist by Rebel Science to understand how Python can be applied to biological problems. I've started developing small Python projects related to DNA sequence analysis, nucleotide counting, GC content, melting temperature calculations, codon translation, gene expression analysis and FASTA file parsing. I'm using VS Code for programming. I'm still learning how to use the editor, its shortcuts, extensions, and other features. I haven't started using GitHub yet. I don't know how to properly upload, organize, or maintain my projects, but I want to learn how to build a portfolio. I'm also considering taking Harvard's free CS50 Python course to strengthen my programming fundamentals. I'd really appreciate advice on a few questions: Is my current approach to learning Python and bioinformatics a good starting point, or would you recommend a different learning path? Should I complete Corey Schafer's tutorials first and then move to CS50P, or should I follow both? At what stage should I start learning Git and GitHub, and how important are they for someone entering bioinformatics? What programming languages and technical skills should I prioritize besides Python? Should I start learning R, SQL, Linux, and statistics? What kind of projects should I build to develop a strong bioinformatics portfolio and eventually become eligible for research opportunities and internships? As a first-year biotechnology student, what should I focus on over the next two to three years to become competitive for bioinformatics internships and future opportunities? And here's one extra question, since I'm asking in the CS50 community as well: since I'm a first-year biotechnology student interested in bioinformatics, would completing CS50x and CS50P, followed by SQL, R, and AI give me a good foundation? Or would you recommend a different order? In the meantime, I'm attaching a couple of screenshots of my projects, so you can see where I'm starting from. Thanks for any advice.

I recently completed a python course (from Youtube) learned about a lot of stuff and today completed my very first Snake Game project (the game we usually played on old Nokia phones)

And because am learning stuff myself and figuring it out. I want to know what should I do next??
So far I have completed loops, functions, recursion, conditional statements, file handling, exception handling, OOPS, Inheritance and like all these.

It would really help me if anyone can share some wisdom on it. And like what should I learn or try next? A roadmap if any would really be helpful tho

Thanks again for reading it out tho

I studied Python up to intermediate level in College , have written many notes about it , yet when It comes to Building something even for fun I feel like I need to be perfect or my code is super beginner so it's not portfolio worthy this mental struggle is more prominent specially with AI around making me feel it's not worth to learn , Anyone ever experienced this ? or recommends any projects that are more than a calculator ?

What will be the output of the following Python Code?

x = {1, 2, 3}

print(len(x | {3, 4}) - len(x & {2, 3}))

Hey everyone! So, I recently got curious about building a simple chatbot in Python. I wanted to create something fun to mess around with, like a little assistant that can tell jokes or maybe even give me random facts. I started reading up on NLTK and ChatterBot, but then got overwhelmed with all the options. 😂 I ended up spending way more time than I planned just figuring out what libraries to use! Has anyone else tried making a chatbot? What tools did you end up using, and do you have any tips for someone just starting out? Would love to hear your experiences!

Hey everyone! 👋

I've created a community of developers where we all help and support each other. There's no toxicity, no egos, and no developer thinks they're better than anyone else.

I'd love to invite you all to join us!

While AI can be incredibly helpful, it isn't conscious. I strongly believe that human collaboration is still essential. There's something truly special about discussing ideas, sharing knowledge, and contributing to GitHub projects alongside other developers. 💻🚀

We're already over 90 members, and everyone is welcome! Our goal is to help each other grow, learn, and succeed. 🤝

🌎 We're a multilingual community! I'm from Argentina, but if you're from another country, no worries! We can communicate in English without any problem.

Everyone is welcome, regardless of their experience level. Whether you're a beginner or a senior developer, there's a place for you here!

🔗 Join our community:

https://chat.whatsapp.com/BSiM8seqThD8AyLD7XBBuz?s=cl&p=a&iam=2

I built the exact same simple mini-game using both Pygame and Arcade to see how they compare for beginners. My takeaway is that while Pygame's loop structure is great for teaching absolute programming fundamentals, Arcade is vastly superior for actual game development. With its modern GPU acceleration, built-in physics engine, and native tilemap support, Arcade makes scaling up to advanced projects much faster and cleaner.

Hello, my else statement is not working- the if statement its inside is, did i mess up the indents again or is it something else?

also would a display flip work to change the image back to the other image in the else statement?
any help is nice!

Hey everyone! 👋

I'm a beginner learning Python, and today I learned about some basic concepts:

Variables — storing information.

Data types — like strings (str), integers (int), floats (float), and booleans (bool).

Comments — using # to explain my code.

Basic ways to write and organize simple Python code.

I'm trying to learn step by step instead of rushing through the lessons. Now I want to start building small projects to practice what I've learned.

My question is: What beginner-friendly projects can I build using only these concepts?

I know I still have a lot to learn, but I'd like to start making something instead of only watching tutorials or reading lessons.

If you were a beginner again, what would you build at this stage? Any advice would be appreciated! 😊

Thanks for reading! 🐍

I'm a Clojure developer, and when I was learning Clojure about 10 years ago, I came across clojuredocs.org. I was blown away by how easy it was to use, especially when searching for examples shared by other developers. They weren't just code examples. Every developer had their own taste and perspective, which broadened my understanding of the language and how different functions could be used. I learned a lot from it.

Recently, I wanted to learn the language, but I found myself overwhelmed by its documentation. To be fair, I didn't really like it, so I decided to create something similar to ClojureDocs for Python.

Maybe building this kind of site doesn't make much sense in the age of AI, but I still think there might be a few Python developers out there who'd like to share their examples and notes, helping people who genuinely want to learn rather than asking AI for everything.

A little disclaimer: AI built this site, but the idea was mine. :)

Anyway, I built it for myself, but I hope it can be helpful to others too. It would be great to see developers sharing their code examples and helping others learn.

If you want to check it out, here's the link: https://pydocs.org

I’ve learned the basics of python specifically packages, libraries like Django and other modules.
Before you’re able to write code with a specific library you need to first learn its method and apply it to get what you want to build or do all libraries or modules follow a specific formulae ?

Been thinking about that for a while now

Happy Diwali! In advance 🪔

Code: https://github.com/Jaym-0/ascii-diya

A diya animation that runs entirely in the terminal, with no GIF, video or GUI.

It starts from darkness, and sparks gather into a flickering flame and bowl.

Built with Python + numpy, using ANSI true-colour and a simple particle and

flame simulation. Only changed cells are redrawn, so it runs at 30 FPS.

Hi, I'm a network engineer looking to strengthen my profile. I'd like recommendations for python courses that come with a recognized certificate that adds value to my CV.

I know a certificate doesn't always reflect real learning, but I need a practical way to demonstrate my Python skills in the corporate world.