Hello, how to find the list element that whether it is on other lists or not? I know by the loop method (found= True). If you know better way please let me know. Thanks. L1 = [1,2,3,4,5] L2=[2,3,6] L3=[1,6,8] L4 = [3,10] result: 1: L1,L3 2: L1,L2 3: L1,L2,L4 6: L2,L3