Python hacks: practical shortcuts that save you time

If you write Python every day, small tricks add up. Here are concise, useful hacks you can use immediately — no theory, just stuff that makes your code cleaner and your workflow faster.

Quick one-liners and useful idioms

Use enumerate when you need an index: for i, v in enumerate(items): — no manual counter. Zip pairs lists cleanly: for a, b in zip(list1, list2):. Prefer join over repeated string concatenation: result = ",".join(parts).

List comprehensions and generator expressions are faster and clearer than loops for simple transforms. If you don’t need the whole list, use a generator: sum(x*x for x in numbers). For grouped counts, use collections.Counter instead of manual dict increments.

Default values are easy with dict.get or collections.defaultdict. Example: counts = defaultdict(int); counts[key] += 1. For one-time assignment inside expressions try the walrus operator: if (n := len(items)) > 10:.

F-strings make formatting readable: f"User {name} has {count} items". Use pathlib.Path for file paths — it’s simpler and cross-platform: p = Path('data') / 'file.txt'.

Debugging, tools, and workflow

When bugs appear, read the traceback top to bottom. Use pdb or ipdb to inspect state: import pdb; pdb.set_trace(). For faster prints, try logging with levels (logging.debug/info) so you can toggle verbosity without changing code.

Measure hotspots with cProfile and micro-benchmarks with timeit. Don’t guess where slowness is — profile. For memory issues, memory_profiler shows line-by-line usage.

Keep environments tidy: use venv or pipx for single tools. Lock dependencies with pip freeze > requirements.txt or use Poetry for reproducible installs. Auto-format with black and lint with flake8 to avoid style debates.

Write small tests early. A couple of pytest tests save hours later. Use type hints for clarity and catch simple mistakes with mypy. Types won’t solve all bugs, but they catch many common problems quickly.

Finally, reuse the standard library. Modules like itertools, functools, csv, and json often remove the need for third-party code. When you do add packages, pick well-documented ones and pin versions.

Try one or two of these hacks today. Tweak your editor shortcuts, add a linting step, or swap a loop for a comprehension — small changes yield big wins.