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How do you access details about the exception currently being handled, like its type, value, and traceback, using sys.exc_info()? How does the 'else' clause on a try statement work, and what's its purpose compared to just putting that code at the end of 'try'? How does Python 3.11's exception groups (ExceptionGroup) and the 'except*' syntax let you handle MULTIPLE unrelated exceptions raised together? How would you design a custom exception HIERARCHY for an application, and why does this matter for how callers can catch errors at different granularities? How would you implement a retry-with-backoff decorator that catches specific transient exceptions and retries with increasing delays? How does exception performance (raising/catching) compare to normal control flow, and why does Python's EAFP style still encourage using exceptions for routine control flow, unlike some other languages? How would you write a context manager using @contextlib.contextmanager that both sets up a resource AND properly handles/logs any exception that occurs while it's in use? How would you implement a circuit breaker pattern using exception handling, to stop repeatedly calling a service that's consistently failing?
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How does context manager __exit__ interact with exception handling, and how can it SUPPRESS an exception by returning True?

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Answer

__exit__(self, exc_type, exc_value, traceback) receives details of any exception raised inside the 'with' block; if it returns a TRUTHY value, the exception is SUPPRESSED entirely (treated as handled, execution continues after the 'with' block) — returning None/False (the default) lets the exception propagate normally.
class SuppressErrors:
    def __enter__(self):
        return self
    def __exit__(self, exc_type, exc_value, tb):
        if exc_type is ValueError:
            print(f"Suppressed: {exc_value}")
            return True  # suppresses the ValueError
        return False  # lets other exception types propagate normally

with SuppressErrors():
    raise ValueError("this gets suppressed")
print("Execution continues here")
Real-world example Building a custom context manager (similar to contextlib.suppress) that intentionally swallows specific, expected exception types.

Common follow-ups: How does the standard library's contextlib.suppress() context manager provide this exact same capability more concisely?

File I/O & Context Managers
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