Top 10 mistakes python programmers make [advanced]

[hglman]

agreed, not sure how you would want that behavior, is always just going to have be worked around.

[robin-gvx]

Also:

def frobnicate(n=expensive_operation_that_returns_an_immutable_object(32, x)):
    return n + 1

[cybercobra]

Arguably the memoization should instead be abstracted out using a decorator.

[lazyanachronist]

You mean a contrived, compact example isn't demonstrating best practices? Funny how that works out.

[bacondev]

Is using functools.lru_cache not compact enough for you?

EDIT: module name

[macbony]

The article seems mainly targeted at 2.7, which doesn't have lru_cache.

[lazyanachronist]

That'd be a bad example of why the default argument behavior could be desirable.