There are three cases when we are talking about this topic.
Case 1: two lists are strictly equal, they have the same size, the elements in the lists have same order, and all corresponding pairs of elements in the two lists are equal;
Case 2: two lists containing the same elements, they have the same size, and there are duplicate elements within the lists. However, the number of counts each element appears in the two lists must be the same.
Case 3: two lists containing the same elements, regardless of element orders or whether the elements have the same duplication counts.