$ python
>>> lst1 = [1, 2, 3]
>>> lst2 = [1, 2, 3]
>>> lst1 == lst2
True
>>> lst1 is lst2
False
>>> lst3 = lst1
>>> lst3 is lst1
True
>>> set([1, 2, 3])
set([1, 2, 3])
>>> set([1, 2, 3]) == [1, 2, 3]
False
>>> lst4 = [lst1, lst2]
>>> lst5 = [lst1, lst2]
>>> lst4 == lst5
True
>>> lst4 is lst5
False
>>> lst4[0] == lst5[0]
True
>>> lst4[0] is lst5[0]
True
>>> 













>>> lst1 = []
>>> lst2 = []
>>> lst1.append(lst2)
>>> lst2.append(lst1)
>>> lst1
[[[...]]]
>>> lst2
[[[...]]]
>>> lst1 is lst2
False
>>> lst1 == lst2
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
RuntimeError: maximum recursion depth exceeded in cmp
>>>