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Why is a bare 'except:' clause (catching everything with no type specified) generally discouraged? How do you create a custom exception class, and what's the minimal amount of code needed? What is the difference between 'raise' and 'raise ... from ...' for exception chaining? How do you access details about the exception currently being handled, like its type, value, and traceback, using sys.exc_info()? 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 does context manager __exit__ interact with exception handling, and how can it SUPPRESS an exception by returning True? 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?
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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'?

Intermediate

Answer

The 'else' clause runs ONLY if the 'try' block completed WITHOUT raising any exception — putting code there (instead of at the end of 'try') makes it explicit that this code is NOT meant to be protected by the except clauses, avoiding accidentally catching exceptions from code that wasn't the original risky operation.
try:
    value = risky_parse(data)
except ValueError:
    print("Parsing failed")
else:
    print(f"Parsed successfully: {value}")  # only runs if risky_parse succeeded, and its own errors aren't caught above
Real-world example Clearly separating the 'risky' operation being protected from subsequent code that shouldn't accidentally have its own errors caught by the same except clause.

Common follow-ups: What would go wrong if the 'else' block's code were instead placed at the END of the 'try' block?

Debugging & Profiling
All 15 Exception Handling questions