The class collections.defaultdict takes a default factory, used to generate a default value.
If the values contained in the dict-like object should default to False, the instance can be created as:
d_false = defaultdict(bool)
What is the most pythonic way to achieve the same for a default value of True?
In other terms, is there a standard callable object returning True which is idiomatically used as the relative of bool?
Of course, the factory could be built as a lambda expression:
d_true = defaultdict(lambda: True)
but this might be reinventing the wheel.
Well, you can do
d = defaultdict(True.__bool__)
but I personally would go with the lambda: True.