('CID100440118', 2),N,O6-Disulfo-Glucosamine
('CID100440118', 2),N,O6-DISULFO-GLUCOSAMINE
('CID100000489', 1),N,O6-Disulfo-Glucosamine
ldiff: defaultdict(<type 'list'>, {'CID100440118': [0, 0], 'CID100000489': [0]})
f1: [0, 0]
f2: [0]
c1: Counter({0: 2})
c2: Counter({0: 1})
The chosen was ... CID100440118