Find duplicate items within a list of list of tuples Python

Question

I want to find the matching item from the below given list.My List may be super large.

The very first item in the tuple \"N1_10\" is duplicated and matched with anot

Answer 1

Does output order matter? This is the simplest way I could think of:

ListA  = [[('N1_10', 'N2_28'), ('N1_35', 'N2_44')],[('N1_22', 'N3_72'), ('N1_10', 'N3_98')],
            [('N2_33', 'N3_28'), ('N2_55', 'N3_62'), ('N2_61', 'N3_37')]]

idx = dict()

for sublist in ListA:
    for pair in sublist:
        for item in pair:
            mapping = idx.get(item,set())
            mapping.update(pair)
            idx[item] = mapping 
            for subitem in mapping:
                submapping = idx.get(subitem,set())
                submapping.update(mapping)
                idx[subitem] = submapping


for x in set([frozenset(x) for x in idx.values()]):
    print list(x)

Output:

['N3_72', 'N1_22']
['N2_28', 'N3_98', 'N1_10']
['N2_61', 'N3_37']
['N2_33', 'N3_28']
['N2_55', 'N3_62']
['N2_44', 'N1_35']