ExitStack & Exception Groups — Series 2

Preview — 3 of 10 questions

What is the output of the following code?

javascript

class Wrapper:
    def __enter__(self):
        return "not self"

    def __exit__(self, *args):
        pass

with Wrapper() as w:
    print(w)
    print(type(w))

Anot self, <class 'str'>

B<__main__.Wrapper object at 0x...>, <class '__main__.Wrapper'> — as w always binds to the context manager instance itself, regardless of what __enter__ returns.

CNone, <class 'NoneType'>

DTypeError: __enter__() must return self

What is the output of the following code?

javascript

import io
from contextlib import redirect_stdout

buffer = io.StringIO()
with redirect_stdout(buffer):
    print("captured!")

print("normal output")
print(repr(buffer.getvalue()))

Acaptured!, then 'normal output\n' — redirect_stdout swaps which stream is captured vs. printed normally.

Bnormal output, 'captured!\n'

Cnormal output, '' — redirect_stdout discards output entirely instead of capturing it.

DTypeError: redirect_stdout() missing required argument

What is the output of the following code?

javascript

try:
    raise ExceptionGroup("multi", [ValueError("v"), TypeError("t"), KeyError("k")])
except* (ValueError, TypeError) as eg:
    print("caught:", sorted(str(e) for e in eg.exceptions))
except* KeyError as eg:
    print("key error:", eg.exceptions)

Acaught: ['v'], then caught: ['t'], then key error: (KeyError('k'),) — except* can only ever match one exception type per clause, even when a tuple is given.

BTypeError: except* does not accept a tuple of exception types

Ccaught: ['t', 'v'], key error: (KeyError('k'),)

Dkey error: (KeyError('k'),) only — the first except* clause silently absorbs everything and never prints, since a tuple type always matches greedily.

Answer all 10 questions (7 more), see explanations for every answer, and track your score.