('CID107504988', 2),beta-Hydroxyfentanyl
('CID107504988', 2),Beta-hydroxyfentanyl
('CID100062278', 1),beta-Hydroxyfentanyl
ldiff: defaultdict(<type 'list'>, {'CID107504988': [0, 0], 'CID100062278': [0]})
f1: [0, 0]
f2: [0]
c1: Counter({0: 2})
c2: Counter({0: 1})
The chosen was ... CID107504988