dic = {'bsx_8612': [23, 567, 632], 'asd_6375': [654, 12, 962], 'asd_2498': [56, 12, 574], 'bsx_9344': [96, 1022, 324]}
print max(dic.items(), key = lambda (k, v): sum(v))[0]
# Python 3
print max(dic.items(), key = lambda t: sum(t[1]))[0]
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