> tying methods with the individual/first argument makes it very difficult to model interactions of multiple objects. The best example of this in Python is ope

> tying methods with the individual/first argument makes it very difficult to model interactions of multiple objects. The best example of this in Python is operator overloading. We need to define both `__add__` and `__radd__` methods to overload a single operator. Even then, there are situations where Python will call one of those where the other would be better.