def fromkeys(cls, seq, values=None):
        """
        Create a new DictSet with keys from seq and values set to
        set(values). When values is not supplied the values are
        initialized as empty sets.
        """
        d = cls()
        for key in seq:
            if values == None:
                d[key] = set()
            else:
                d[key] = set(values)
                
        return d

        Create a new DictSet with keys from seq and values set to
        set(values). When values is not supplied the values are
        initialized as empty sets.
        
recipes/Python/577702_DictSet__specialized_Pythcontainer_datatype/recipe-577702.py