Python中的“全部”功能如何工作？

Question

I searched for understanding about the all function in Python, and I found this , according to here:

all will return True only when all the elements are Truthy.

But when I work with this function it's acting differently:

'?' == True   # False
'!' == True   # False
all(['?','!']) # True

Why is it that when all elements in input are False it returns True ? Did I misunderstand its functionality or is there an explanation?

Answer 1

only when all the elements are Truthy .

Truthy != True .

all essentially checks whether bool(something) is True (for all something s in the iterable).

>>> "?" == True
False
>>> "?" == False # it's not False either
False
>>> bool("?")
True

Answer 2

'?' and '!' are both truthy since they are non-empty Strings.

There's a difference between True and "truthy". Truthy means that when coerced, it can evaluate to True . That's different from it being == to True though.

Answer 3

all() function is used when we want to check that if all the items in a list are iterable or not. For ex : x=[1,2,3,4,5] all(x) It will return True.