15 Python Best Practices Developers Must Know

Robert Raphaël
5 min readMar 31, 2023
Developer from undraw

As a passionate Python developer, I have learned the hard way that writing good code is not just about getting the job done, but also about writing code that is readable, maintainable, and scalable. In this article, I will share 15 Python best practices that every developer should know.

1) Write Pythonic code

Pythonic code is code that follows the conventions and idioms of the Python language. For example, using list comprehensions instead of for loops, using context managers to manage resources, and using decorators to add functionality to functions.

2) Use PEP8 guidelines

PEP8 is the official style guide for Python code. It includes guidelines for things like naming conventions, code layout, and code formatting. Following PEP8 makes your code more readable and easier to understand.

# Use snake_case for variable names
my_variable = 42

# Use 4 spaces for indentation
def my_function():
if x > 0:
print('x is positive')
else:
print('x is not positive')

3) Use virtual environments

Virtual environments allow you to create isolated Python environments for each project. This makes it easy to manage dependencies and ensures that your code runs consistently across different environments. You can use venv or conda for example.

# Create a virtual environment
python3 -m venv myenv

# Activate the virtual environment
source myenv/bin/activate

# Install packages in the virtual environment
pip install requests

4) Use a package manager

A package manager like pip or conda makes it easy to manage your project’s dependencies. You can use it to install, upgrade, and remove packages, and ensure that everyone working on the project is using the same versions of the dependencies.

# Install a package
pip install pandas

# Upgrade a package
pip install --upgrade pandas

# Remove a package
pip uninstall pandas

5) Write unit tests

Unit tests are automated tests that check the behavior of a specific piece of code. They help ensure that your code works as expected and make it easy to catch bugs early.

# Define a unit test
import unittest

class MyTest(unittest.TestCase):
def test_add(self):
self.assertEqual(add(2, 2), 4)

6) Use meaningful variable and function names

Use descriptive and meaningful names for your variables and functions. This makes it easier for others to understand your code and reduces the likelihood of introducing bugs.

# Use descriptive names
total_sales = 1000000

def calculate_sales_tax(total):
return total * 0.05

7) Use docstrings

Docstrings are comments that provide documentation for your code. They describe the purpose of functions, classes, and modules, and provide usage examples. This makes it easy for others to understand and use your code.

# Use docstrings to document your code
def greet(name):
"""
Greets the user by name.
"""
print(f'Hello, {name}!')

8) Use version control

Version control systems like Git help you manage changes to your code over time. You can use them to track changes, collaborate with others, and revert to previous versions of your code.

# Initialize a Git repository
git init

# Add files to the repository
git add my_file.py

# Commit changes to the repository
git commit -m "Added a new feature"

9) Keep your code simple

Write simple and straightforward code that does one thing and does it well. Avoid unnecessary complexity and keep your code as concise as possible.

# Write simple code that does one thing
def double(x):
return x * 2

10) Handle exceptions gracefully

Always handle exceptions in your code and provide meaningful error messages to help users understand what went wrong. Use try/except blocks to handle exceptions and avoid catching exceptions that you don’t know how to handle.

# Use try/except blocks to handle exceptions
try:
result = divide(10, 0)
except ZeroDivisionError:
print('Cannot divide by zero')

11) Don’t repeat yourself (DRY)

Don’t repeat code that can be reused. Use functions, classes, and modules to modularize your code and reduce redundancy.

# Use functions to reduce redundancy
def calculate_area(radius):
return 3.14 * radius**2

def calculate_volume(radius, height):
return calculate_area(radius) * height

12) Use context managers

Context managers are a way to manage resources like files, sockets, and database connections. They ensure that resources are properly closed when they are no longer needed, and reduce the likelihood of resource leaks.

# Use context managers to manage resources
with open('file.txt', 'r') as f:
data = f.read()

13) Use decorators

Decorators are a way to add functionality to functions and classes without modifying their source code. They can be used to add cross-cutting concerns like logging, caching, or authentication.

# Use decorators to add functionality to functions
def log_calls(func):
def wrapper(*args, **kwargs):
result = func(*args, **kwargs)
print(f'{func.__name__} called with {args} {kwargs} and returned {result}')
return result
return wrapper

@log_calls
def add(x, y):
return x + y

14) Use list comprehensions

List comprehensions are a concise way to create lists from other iterables. They are more efficient and more readable than using loops and appending to a list.

# Use list comprehensions to simplify code
numbers = [1, 2, 3, 4, 5]
squares = [x**2 for x in numbers if x % 2 == 0]

15) Use generators

Generators are a way to create iterators that generate values on the fly. They are more memory-efficient than creating lists or other collections, and can help improve the performance of your code.

def fibonacci():
a, b = 0, 1
while True:
yield a
a, b = b, a + b

# Print the first 10 Fibonacci numbers
for i, n in enumerate(fibonacci()):
if i == 10:
break
print(n)

Bonus : Keep up with best practices

# Stay up to date with the latest best practices
# Check out the Python Enhancement Proposals (PEPs) for new features and improvements
# Read articles and books on Python programming
# Attend Python conferences and meetups to learn from other developers

In summary, following these best practices can help you write cleaner, more efficient, and more maintainable Python code. By writing Pythonic code, using virtual environments and package managers, writing unit tests, using meaningful names, and handling exceptions gracefully, you can create code that is easier to read, debug, and maintain. Additionally, using context managers, decorators, and list comprehensions can simplify your code and make it more elegant. Finally, by staying up to date with best practices and continuing to learn and improve your skills, you can become a better Python developer and contribute to the community.

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Robert Raphaël
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I am multi-skilled, passionate and I always looking for new challenges about new technologies..