如何将某些行添加到2D矩阵？

# 原始矩阵
matrix = [
    [1, 2, 3],
    [4, 5, 6],
    [7, 8, 9]
]

# 要添加的行
new_rows = [
    [10, 11, 12],
    [13, 14, 15]
]

# 创建新矩阵
new_matrix = []

# 复制原始矩阵的所有行到新矩阵
for row in matrix:
    new_matrix.append(row)

# 将要添加的行插入到新矩阵的末尾
for row in new_rows:
    new_matrix.append(row)

# 打印新矩阵
for row in new_matrix:
    print(row)