为什么是【2】【3】求解析

# 相当于

for j in range(1, 6):
    row = []
    for i in range(1, 6):
        row.append((i, j))
    print(row)

'''--result
[(1, 1), (2, 1), (3, 1), (4, 1), (5, 1)]
[(1, 2), (2, 2), (3, 2), (4, 2), (5, 2)]
[(1, 3), (2, 3), (3, 3), (4, 3), (5, 3)]
[(1, 4), (2, 4), (3, 4), (4, 4), (5, 4)]
[(1, 5), (2, 5), (3, 5), (4, 5), (5, 5)]
'''