What is the next step in python debugging after print statements?

[LarryEW]

I'm stuck on a python debugging problem where my script runs but gives the wrong output. I've used print statements to check values. What's the next logical step when print debugging isn't enough to find the issue?

[Zoey90]

Try a real debugger and put away print debugging for good.

[Anthony.D]

Use a debugger like pdb or VSCode to step through line by line. Set breakpoints where output diverges, inspect variables, and watch expressions. Log exact values at key steps so you can confirm what actually changes.

[GeorgeA]

If you still can’t spot the issue, build a tiny reproducible test around the behavior. A script with fixed inputs that prints only the outputs helps isolate the logic. Run it under a debugger and check the stack trace to see how data moves between functions. Add lightweight asserts and replace stubborn print statements with logging to keep a clean trace.

[JohnL]

Beyond the basics, a thorough plan helps when the bug hides in subtle places. Narrow down the specific input that yields the wrong output and extract a small function that reproduces it. Run that under a debugger with breakpoints on entry and exit and watch how each variable evolves. If you’re not already, switch off print statements and replace them with structured logging so traces stay readable. Use assertions to codify invariants and check types where possible. Look for off by one errors, mutable defaults, or unintended side effects from global state. Confirm external data sources or configs aren’t changing behind your back. If there’s randomness or time-based values, seed or freeze them during tests. If you get an exception, read the error message and stack trace; if not, let the debugger show you the call stack and where the divergence starts. Finally, add a regression test so future changes can’t reintroduce the bug and run the full test suite to confirm everything still behaves as intended.