>>> l1 = [1,2,3]
>>> l2 = l1
>>> l2
[1, 2, 3]
>>> l1.append(4)
>>> l1
[1, 2, 3, 4]
>>> l2
[1, 2, 3, 4]
In above l2 list updated automatically.
Case 2:
>>> a=10
>>> b=a
>>> a = a+5
>>> a
15
>>> b
10
but here b never changed. What is the difference between these list and other data structure properties.