I was basically trying to make explicit the following current behavior:

```
>>> np.bincount(list=[3,4,5])
array([0, 0, 0, 1, 1, 1], dtype=int64)
```

Internally, the first argument is a kwarg with label `list`. I agree that it is an unfortunate choice, and will change it both internally and in the docstring to `arr`. Since it is an undocumented feature, I understand this change can be made with out worries, right?