The error that still worked Hard

What does this print?

t = ([1],)
try:
    t[0] += [2]
except TypeError:
    pass
print(t)

A([1, 2],)
B([2],)
C([1],)
Draises TypeError

Show the answer

A: ([1, 2],)

Why: += on a list does two things: it extends the list in place, then assigns the result back into the tuple. The extend succeeds; the assignment fails, because tuples cannot be assigned to. The list inside was already changed.

Learn it: Tuples ↗ Run it yourself ↗

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