('CID100000426', 1),D-Glutamicacid, N-[4-[(aminoiminomethyl)amino]-1-carboxybutyl]-, (S)-
('CID100102871', 1),D-Glutamicacid, 4-fluoro-, threo-
ldiff: defaultdict(<type 'list'>, {'CID100000426': [55], 'CID100102871': [19]})
f1: [55]
f2: [19]
c1: Counter({55: 1})
c2: Counter({19: 1})
The chosen was  ... CID100102871