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bool

Return a Boolean value, either True or False.

Description

The bool class is a subclass of int. It converts a value to a Boolean using the standard truth testing procedure. If the value is omitted or false, it returns False; otherwise it returns True.

The bool class has only two instances: True and False. These are the only Boolean values in Python. When converting values, the following are considered false: None, False, zero of any numeric type, empty sequences, and empty mappings.

Custom objects can define their truth value by implementing the __bool__() method. If __bool__() is not defined, __len__() is consulted, and the object is considered true if its length is nonzero.

Arguments

NameDescriptionOptional
x A value to convert to a Boolean. Yes

Example

bool(0)  # Returns False
bool(1)  # Returns True
bool([])  # Returns False

Reference