Why does this change two zeroes to 5 instead of just the first one?

Question

a = [[0]*2]*2
a[0][0] = 5
print(a)
#[5,0][5,0]

Answer 1

print(n*list) prints n representations of the same list.

Likewise, a = [[0]*2]*2 creates a nested list with two inner lists that are the same. If you change one, you change the other one as well.

Use a = [[0 for i in range(2)] for j in range(2)] to create a nested list with two independent inner lists.

Answer 2

Thanks again! Anna