In [ ]:

    

class Interface(type):
    def __init__(cls, classname, bases, classdict):
        super().__init__(classname, bases, classdict)
        implements = set(dir(cls))
        
        for interface_attributes, interface_class in ((set(dir(interface)), interface) for interface in cls.__interfaces__):
            if not implements >= interface_attributes:
                missing_attributes = str(interface_attributes - implements)
                raise AttributeError("In {} is missing: {}".format(interface_class, missing_attributes))
    
class IPunkt():
    x = 5
    y = 10
    
    def odleglosc(self):
        pass
    
class Punkt(object, metaclass=Interface):
    __interfaces__ = [ IPunkt]
    
    x = 1
    y = 2
    
    def __init__(self, x, y):
        self.x = x
        self.y = y
        
    def odleglosc(self):
        pass
        
p = Punkt(1, 2)