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unpacked-list-comprehension (UP027)#

Derived from the pyupgrade linter.

Warning: This rule is deprecated and will be removed in a future release.

Fix is always available.

Deprecation#

There's no evidence that generators are meaningfully faster than list comprehensions when combined with unpacking.

What it does#

Checks for list comprehensions that are immediately unpacked.

Why is this bad?#

There is no reason to use a list comprehension if the result is immediately unpacked. Instead, use a generator expression, which avoids allocating an intermediary list.

Example#

a, b, c = [foo(x) for x in items]

Use instead:

a, b, c = (foo(x) for x in items)

References#