A Beginner’s Guide to Writing Clean Code in Python

Clean code isn’t just about making it work — it’s about making it readable, maintainable, and beautiful. Here's how I apply it in my Python projects.

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🧠 Why Clean Code Matters

In college, I often wrote Python scripts that “just worked.” But once I started working on real projects like Homes Connect and Krishi Seva Management System, I realized that messy code becomes a nightmare when debugging or collaborating with others. Clean code isn’t optional — it’s a superpower.

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📦 1. Structure Your Files

Even in small projects, use folders and naming conventions:

• main.py: Entry point
• utils/: Helper functions
• services/: Core logic or API calls
• tests/: Unit test files

Example: In my automation scripts for React projects, I keep auth-related logic in a separate auth/ module instead of mixing everything into app.py.

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✍️ 2. Use Descriptive Variable and Function Names

Instead of:

x = 10
def f(a):
    return a + x

Write:

discount_rate = 10
def calculate_total(price):
    return price + discount_rate

Your future self (and teammates) will thank you!

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🚫 3. Avoid Hardcoding

In my University Project Bank app, I initially hardcoded project categories. But later I switched to dynamic configurations and environment variables.

Use .env files or config modules:

import os
DB_URL = os.getenv("DATABASE_URL")

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🧹 4. Keep Functions Small and Focused

Functions should do one thing — and do it well. If your function is scrolling off your screen, break it down.

def fetch_user_data(user_id):
    user = db.get_user(user_id)
    logs = db.get_user_logs(user_id)
    return {"user": user, "logs": logs}

Modular functions help in debugging and testing, especially when scaling your backend services like in Express.js and Spring Boot.

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🧪 5. Add Meaningful Comments (But Don’t Overdo It)

Comment why, not what:

# Good
# Refresh the token if it's about to expire
if token.expired():
    token = refresh_token()

Avoid this:

# Check if token is expired
# If yes, then refresh it
# Then assign it back
# Again assign

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🧼 6. Use Linters and Formatters

Tools like Black, Pylint, and flake8 can catch bad practices automatically.

pip install black
black .  # Formats all Python files

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📊 7. Write Tests — Even Basic Ones

In my real estate project (Homes Connect), writing unit tests saved me from breaking login functionality during updates.

import unittest

def add(a, b):
    return a + b

class TestAdd(unittest.TestCase):
    def test_add(self):
        self.assertEqual(add(2, 3), 5)

Even 2-3 tests per module improve confidence and speed up collaboration.

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🧠 Final Thoughts

Writing clean code isn't about perfection — it's about making your code understandable, extendable, and usable by other humans (including future you).

Whether you're building with Flask, React, Node.js, or even PHP like I did in Krishi Seva, the habit of writing clean code will always pay off — during interviews, team reviews, and product launches.

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👨‍💻 Want to see clean code in action? Check out my projects on GitHub or connect with me on LinkedIn.