How does all() in python work on empty lists

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It’s true because for every element in the list, all 0 of them, they all are equal to 2.

You can think of all being implemented as:

def all(my_list, condition):
  for a in my_list:
    if not condition(a):
      return False
  return True

Whereas any is:

def any(my_list, condition):
  for a in my_list:
    if condition(a):
      return True
  return False

That is to say, all is innocent until proven guilty, and any is guilty until proven innocent.

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