('CID100229473', 1),Oxalicacid, bis[2-(2,4-dichlorophenoxy)ethyl] ester (6CI,8CI)
('CID100096146', 1), Oxalicacid bis(benzal hydrazide)
ldiff: defaultdict(<type 'list'>, {'CID100229473': [51], 'CID100096146': [23]})
f1: [51]
f2: [23]
c1: Counter({51: 1})
c2: Counter({23: 1})
The chosen was  ... CID100096146