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← Coursesβ€ΊSenior Deep-DivesModule 6 Β· FAANG-2026 deep divesβ€Ίfunctools.partial vs lambda β€” closure timingpredict113 / 161
+150 XP
Task
πŸ“ **Task:** Predict the exact output. \`mul(a, b, c)\` multiplies three numbers. \`double = partial(mul, 2)\` freezes \`a=2\`. \`with_c = partial(mul, c=10)\` freezes \`c=10\` β€” but watch what happens when the caller ALSO passes \`c=99\`. Then five lines later: list of lambdas vs list of partials over the same loop. Which one captures correctly? πŸ“‹ Implement the function above. Tests run automatically. πŸ’‘ **Hint:** Re-read the theory if you get stuck.
Predict the output

Read the code carefully

from functools import partial


def mul(a, b, c):
    return a * b * c


double = partial(mul, 2)
print(double(3, 4))

with_c = partial(mul, c=10)
print(with_c(2, 3))
print(with_c(2, 3, c=99))


def show(i):
    return i


funcs_lambda = [lambda: i for i in range(3)]
funcs_partial = [partial(show, i) for i in range(3)]

print([f() for f in funcs_lambda])
print([f() for f in funcs_partial])

What will the program print? Write here: