Python return Min Droly списка

a = [[1,0,1,2,1,1,1,3111111], [31,1,4,51,1,1,1], [1,1,6,7,8]]

print min(a, key=len)
# [1, 1, 6, 7, 8]

print len(min(a, key=len))
# 5

print min(map(len, a))
# 5
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