Python bool() built-in function
From the Python 3 documentation
Return a Boolean value, True or False. x is converted using the standard truth testing procedure. If x is false or omitted, this returns False; otherwise, it returns True. The bool class is a subclass of int. It cannot be subclassed further. Its only instances are False and True.
Examples
>>> bool(0)
# False
>>> bool(1)
# True
>>> bool(2)
# True
>>> bool('3')
# True
>>> bool(False)
# False
>>> bool(True)
# True