col_totals = [sum(x) for x in zip(*my_list)]
n,m=int(input()),int(input())
for i in range(0,n):
for j in range(0,m):
a[i].append(int(input()))
>>> b=np.sum(x)
print(b)
21
#create 2D array Matrix 4X4
Matrix = [[0 for i in range(4)] for j in range(4)]
#2D array python
x=[[11, 12,13],[14, 15,16],[17, 18,19]]
sum(sum(x,[]))
>>> x=[[1, 2],[3, 4],[5, 6]]
>>> sum(sum(x,[]))
21