LOL folks that probably equate least lines to "better practice". It is clever for sure though :]

Wowsers, this solution is far cleaner than mine. Thank you for the question!!!

Wowsers, this is really clever. Great job :]

Wowsers. Great solution. Makes mine look like trash xD

Cleanest solution i've seen yet, great job!!

Greetings, thanks for the adding this question!

Quick question, I think the example dictionary has a typo. Specifically, if we look at

dct = {'A3': [('A0', 1), ('A2', 1)], 'A0': [('A3', 1), ('A2', 1)], 'A4': [('A2', 1)], 'A1': [('A2', 1)], 'A2': [('A1', 1), ('A2', 1), ('A3', 1), ('A4', 1)]}

I think dct['A2'] should really be [('A0', 1), ('A1', 1), ('A3', 1), ('A4', 1)].

Thanks!!