('CID120328528', 2),2-bromothiazole; N-heptylformamide
('CID120328528', 2),2-bromo-1,3-thiazole; N-heptylformamide
('CID100347402', 1),N-HEPTYLFORMAMIDE
ldiff: defaultdict(<type 'list'>, {'CID120328528': [17, 22], 'CID100347402': [0]})
f1: [17, 22]
f2: [0]
c1: Counter({17: 1, 22: 1})
c2: Counter({0: 1})
The chosen was  ... CID100347402