Then how can we destroy the 3rd instance, right after its creation and from inside class Moo code? class Moo: cnt = 0 def __init__(self, x): self.x = x self.__class__.cnt += 1 if self.__class__.cnt > 2: print id(self) ## 13406816 ## in what dict is this ID? ## and can we delete it from there? ## ??? f = Moo(1) g = Moo(2) h = Moo(3) print h