('CID100179536', 2),3-(3,4-Dihydroxyphenyl)lacticacid
('CID100179536', 2),Lacticacid, 3-(3,4-dihydroxyphenyl)- (6CI,8CI)
('CID100079041', 2),Lacticacid, acetate, L- (8CI)
('CID100079041', 2),O-Acetyl-(S)-lacticacid
ldiff: defaultdict(<type 'list'>, {'CID100179536': [23, 36], 'CID100079041': [19, 13]})
f1: [23, 36]
f2: [19, 13]
c1: Counter({36: 1, 23: 1})
c2: Counter({19: 1, 13: 1})
The chosen was  ... CID100079041