Gerhard Häring wrote:
len() make it clear that the argument is a sequence.
Not necessarily. Classes that overrides __len__ may fool that assumption (well, in python classes that overrides special functions may do anything it is never intended to do).
I often think an "if item:" as "is item workable?". What the exact definition of "workable" is just something I don't care, at least until I need to debug the code. A container is workable if it contains something; most of the time, an empty sequence does not have any value (pun intended) and thus unworkable.
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