s1 = "ab" s2 = "eidbaoxkt" win_left = 0 win_right = len(s1) s1_permutations = set(s1) while win_right <= len(s2): s2_sub = set(s2[win_left:win_right]) if s1_permutations == set(s2[win_left:win_right]): print("True") # return true win_left += 1 win_right += 1 print("False") # return false