freeCodeCamp/guide/english/python/all-iterable/index.md

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---
title: Python All Iterable
---
`all()` is a built-in function in Python 3 (and Python 2 since version 2.5), to check if all items of an <a href='https://docs.python.org/3/glossary.html#term-iterable' target='_blank' rel='nofollow'>_iterable_</a> are `True`. It takes one argument, `iterable`.
## Argument
### iterable
The `iterable` argument is the collection whose entries are to be checked. It can be a `list`, `str`, `dict`, `tuple`, etc.
## Return Value
The return value is a Boolean. If and only if **all** entries of `iterable` are [truthy](https://guide.freecodecamp.org/python/truth-value-testing), it returns `True`. This function essentially performs a Boolean `AND` operation over all elements.
If even one of them is not truthy, it returns `False`.
The `all()` operation is equivalent to (not internally implemented exactly like this)
def all(iterable):
for element in iterable:
if not element:
return False
return True
## Code Sample
print(all([])) #=> True # Because an empty iterable has no non-truthy elements
print(all([6, 7])) #=> True
print(all([6, 7, None])) #=> False # Because it has None
print(all([0, 6, 7])) #=> False # Because it has zero
print(all([9, 8, [1, 2]])) #=> True
print(all([9, 8, []])) #=> False # Because it has []
print(all([9, 8, [1, 2, []]])) #=> True
print(all([9, 8, {}])) #=> False # Because it has {}
print(all([9, 8, {'engine': 'Gcloud'}])) #=> True
![:rocket:](//forum.freecodecamp.com/images/emoji/emoji_one/rocket.png?v=2 ":rocket:") <a href='https://repl.it/CL9U/0' target='_blank' rel='nofollow'>Run Code</a>
<a href='https://docs.python.org/3/library/functions.html#all' target='_blank' rel='nofollow'>Official Docs</a>