python sum of last n items in list

1test_list = [4, 5, 2, 6, 7, 8, 10] 
2K = 5
3  
4# Inverse K slice Sum using list slicing + sum()
5res = sum(test_list[-K:]) 
6
7print("The last K elements sum of list is : " + str(res)) 
8
9# Result:
10# The last K elements sum of list is : 33