Where Should I Place Try/Except Statements in My Python Code?

I was taught that ideal programming leans towards a contract-based approach. You either program defensively—doing all possible checks and validations—or you state what the function expects through comments and type hints, thus letting users know what to provide. Defensive programming is important mainly when you deal with user input, but once you validate it, the rest can follow contracts.

You should also think about cleanup operations. For example, if a function controls a motor, and something goes wrong in the process, you need a try/except to ensure the motor turns off safely. Python does support a 'finally' clause for such scenarios.

Generally, it's best to handle exceptions where you can do something useful about them. If a function can handle an exception and continue working, it's a good idea to catch it there. If it can’t fix the issue, let the exception bubble up so the caller can address it.

For enterprise applications, you'd usually have a framework to log any exceptions without showing stack traces to users. In simpler scripts, letting errors propagate can be fine. You should definitely use try blocks in critical parts, like database operations, where you can rollback if there's an error.

Handling exceptions at a function level is beneficial because it simplifies debugging. If you catch errors closer to where they occur, you can log specific messages and potentially recover from the issue, making maintenance much easier.