Retrieve an item from a dictionary using an arbitrary object as the key

[abcd]

> You'll need __eq__ for testing if two objects are equivalent, and
> __hash__ for calculating object's hash value.
>
> class Type:
>     def __init__(self, val):
>         self.val = val
>
>     def __eq__(self, other):
>         return self.val == other.val
>
>     def __hash__(self):
>         return hash(self.val)

that's exactly what I needed, thanks.