10 ‘Outdated’ Python Practices You Need to Stop Using Right Now

These habits are slowing down your code, confusing your team, and holding you back. Here’s what to do instead.

10 ‘Outdated’ Python Practices You Need to Stop Using Right Now
Photo by cody gallo on Unsplash

Stop writing Python like it’s still 2010.

10 ‘Outdated’ Python Practices You Need to Stop Using Right Now

Python has changed — a lot. But many developers are still writing it like it’s stuck in the early 2010s.

Maybe you copied patterns from an old Stack Overflow post. Or maybe you’ve just been reusing the same code for years without questioning it. Either way, outdated practices can silently kill your productivity, readability, and performance.

This article dives into 10 Python habits that were once common (and maybe even correct) but are now considered harmful, suboptimal, or just plain ugly.

If you want to level up your Python game and write cleaner, more modern code, start by unlearning these.


1. Using range(len(list)) Instead of enumerate()

Old way:

for i in range(len(my_list)): 
    print(i, my_list[i])

Better way:

for i, item in enumerate(my_list): 
    print(i, item)

Using range(len(...)) is more verbose, less readable, and error-prone. enumerate() is Pythonic, clean, and clear.

2. Writing try-except for Flow Control

Old habit:

try: 
    value = my_dict['key'] 
except KeyError: 
    value = 'default'

Better

value = my_dict.get('key', 'default')

Using exceptions for expected behavior is inefficient and messy. get() is the clean way for default lookups.

3. Relying on print() for Debugging

Still using print() statements to debug? You're not alone—but it's time to stop.

Modern alternatives:

  • breakpoint() — built-in since Python 3.7
  • Logging (import logging)
  • VS Code / PyCharm debuggers

print() debugging doesn’t scale. Real tools give you breakpoints, stack traces, and variable inspection—without cluttering your codebase.

4. Using == None Instead of is None

Wrong:

if value == None:

Right:

if value is None:

is None checks identity, which is the correct way to test against None. == None can lead to weird bugs, especially with custom objects.

5. Overusing lambda for Everything

Example:

sorted(data, key=lambda x: x[1])

This is fine in small doses — but avoid using lambdas for anything more than a single, obvious expression. If the logic gets even slightly complex, define a named function.

Better:

def sort_by_value(item): 
    return item[1] 
 
sorted(data, key=sort_by_value)

Too many lambdas make code hard to debug and understand. Python favors readability over cleverness.

6. Writing Utility Classes with Only Static Methods

class Utils: 
    @staticmethod 
    def add(x, y): 
        return x + y

Why did you make a class just to group functions? This is just Java bleed-through.

Better:

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

Or group related functions in a module, not a class.

This is an anti-pattern in Python. You don’t need a class unless you’re storing state or building a reusable interface.

7. Not Using Type Hints

Skipping type hints might save time now — but it’ll cost you later.

Old way:

def process(data): 
    ...

Modern way:

def process(data: list[str]) -> int: 
    ...

Python 3.5+ supports type hints, and tools like MyPy and Pyright make your code safer, more predictable, and easier to understand.

8. Using open(...).read() Without a Context Manager

Old way:

data = open('file.txt').read()

Better:

with open('file.txt') as f: 
    data = f.read()

Using with ensures files are properly closed, even if something goes wrong. It’s safer and more professional.

9. Manually Building Strings Instead of f-Strings

Old way:

'Hello, ' + name + '! You have ' + str(count) + ' messages.'

Better:

f'Hello, {name}! You have {count} messages.'

F-strings (introduced in Python 3.6) are faster, cleaner, and more readable. There’s no excuse not to use them.

10. Writing Python 2 Style Code

It’s been years since Python 2’s end-of-life (January 1, 2020), but its ghost still haunts some codebases.

Signs you’re stuck in the past:

  • Using print without parentheses
  • xrange instead of range
  • dict.iteritems() instead of dict.items()

Why it’s outdated:
There’s no excuse left to write Python 2-style code. If you’re maintaining legacy systems, fine. But for everything else — write modern Python.


Final Thoughts: Evolve With Python or Fall Behind

Python is one of the fastest-evolving languages in the world. New versions add powerful features, cleaner syntax, and better tooling. But you won’t benefit from any of it if you keep writing code like it’s 2012.

Modern Python is beautiful — if you write it right.

So take a look at your current habits. Which of these outdated practices are you still using?

Then do yourself (and your teammates) a favor: upgrade your style, one refactor at a time.


If you found this helpful, follow me for more practical Python tips that actually make you better.

Photo by Mitch on Unsplash