onetoonemap

This is a python module that implements a 1:1 mapping type - similar to a dict, but as well as looking up values by keys (m[k] -> v), you can look up keys by values (m[v] -> k).

Given m = OneToOneMap(), the following constraints are always true:

m.get(key) == value
m.get(value) == key

m.keys() == set(m.keys())
m.values() == set(m.values())
set(m.keys()) & set(m.values()) == set()
set.(m.keys()).isdisjoint(set(m.values())) == True