def __init__(self, factory, takes_self=False):
        """
        `Factory` is part of the default machinery so if we want a default
        value here, we have to implement it ourselves.
        """
        self.factory = factory
        self.takes_self = takes_self

        `Factory` is part of the default machinery so if we want a default
        value here, we have to implement it ourselves.
        
stackoverflow/venv/lib/python3.6/site-packages/attr/_make.py