why in following example appending big_l in for loop changes last lists added big_l?
l=[1,2,3,4,5] big_l=[] def f(ll): x=ll.pop(0) ll.append(x) return ll in range(4): big_l.append(l) print l,big_l l=f(l) it prints:
[1, 2, 3, 4, 5] - [[1, 2, 3, 4, 5]] [2, 3, 4, 5, 1] - [[2, 3, 4, 5, 1], [2, 3, 4, 5, 1]] [3, 4, 5, 1, 2] - [[3, 4, 5, 1, 2], [3, 4, 5, 1, 2], [3, 4, 5, 1, 2]] [4, 5, 1, 2, 3] - [[4, 5, 1, 2, 3], [4, 5, 1, 2, 3], [4, 5, 1, 2, 3], [4, 5, 1, 2, 3]]
