I think one should use `super` in cases like these, so that if people make a subclass like `class myclass(Longitude, AnotherClass)`, it will continue to work. So, I would suggest replacing this with something along the lines of
```
object_state = list(super(Longitude, self).__reduce__())
object_state[2] = (object_state[2], self.wrap_angle)
```
Note that of course now one does not have to include `self._unit` any more in the pickle, since the `super` call goes to `Quantity`, which already includes it (and which should of course also do a `super`). In `__setstate__`, one would then have
```
super_state, own_state = state
super(Longitude, self).__setstate__(super_state)
self.wrap_angle = own_state
```