Quick Tips · Tip 01 · 0:21
Python debugging tip: print the variable name with its value
Put one = inside an f-string: f"{total=}" prints total=550. It also works with expressions and formats, like len(rows)=3 and rate=12.5% (Python 3.8+).
Key moments
What you’ll needPython 3.8+
What you’ll need
- python.org/downloads →
Python 3.8 or newerRuns the code. Check yours with python3 --version. - code.visualstudio.com →
VS Code or CursorEither works; so does any editor you like. - git-scm.com/downloads →
gitOptional for a tip: to keep your own copy of the code. - No packages needed: it uses only the Python standard library.
Set it up
- 1Make a virtual environmentIt keeps this project's packages separate from the rest of your computer.
python3 -m venv .venv source .venv/bin/activate
- 2Run itSave the snippet below as debug.py.
python3 debug.py
debug.pyOpen on GitHub →
rows = [120, 340, 90]
total = sum(rows)
rate = total / 4400
print(total)
print(f"{total=}")
print(f"{len(rows)=} {rate=:.1%}")Transcript
Stop printing bare variables. Which number is that? Add an equals sign in the f-string, and you get the name and value. Expressions and format specs work too.
Total equals 550. Rate, 12.5 percent. Needs Python 3.
8. Name your prints.
Read the lesson on GitHub →- #python
- #pythontips
- #coding
- #programming
