Method fromkeys

pattern/vector/__init__.py:137–138

(cls, k, default=None)

        dict.__init__(self, *args, **kwargs)
    @classmethod
    def fromkeys(cls, k, default=None):
        return readonlydict((k, default) for k in k)
    def copy(self):
        return readonlydict(self)
    def __setitem__(self, k, v):