Django comparing model instances for equality

Question

I understand that, with a singleton situation, you can perform such an operation as:

spam == eggs

and if spam and eggs

Answer 1

As orokusaki comments, "if neither instance has a primary key, it will return true always". If you want this to work, you could extend your model like so:

def __eq__(self, other):
    eq = isinstance(other, self.__class__) and self._get_pk_val() == other._get_pk_val()

    if eq and self._get_pk_val() is None:
        return id(self) == id(other)
    return eq