('CID100002219', 4),D-xylitol 5-(dihydrogen phosphate)
('CID100002219', 4),D-Xylitol 5-phosphate
('CID100002219', 4),D-XYLITOL-5-PHOSPHATE
('CID100002219', 4),D-Xylitol 5-phosphate
('CID100086526', 3),(5S)-5-C-(4-carboxy-1,3-thiazolidin-2-yl)-D-xylitol
('CID100086526', 3),(5S)-5-C-(4-Carboxy-2-thiazolidinyl)-D-xylitol
('CID100086526', 3),D-Xylitol, 5-C-(4-carboxy-2-thiazolidinyl)-, (5S)-
ldiff: defaultdict(<type 'list'>, {'CID100086526': [42, 37, 41], 'CID100002219': [25, 12, 12, 12]})
f1: [25, 12, 12, 12]
f2: [42, 37, 41]
c1: Counter({12: 3, 25: 1})
c2: Counter({41: 1, 42: 1, 37: 1})
The chosen was ... CID100002219