Data structure to implement a dictionary with multiple indexes?

Question

I am looking for a data structure that holds the same values under two different indexes, where I can access the data by either one.

Exampl

Answer 1

Is there a particular reason you can't just use a dictionary:

x = {}
x[1] = x['karl'] = dog
x[2] = x['lisa'] = cat

Then you can access it by either.

If you really don't want to repeat your self you do this:

class MysticalDataStructure(dict):
    def add(self, key1, key2, value):
        return self[key1] = self[key2] = value

x = MysticalDataStructure()
x.add(1, 'karl', dog)
x.add(2, 'lisa', cat)