如何在Julia中漂亮地打印矩阵到字符串？

function print_matrix(matrix)
    rows, cols = size(matrix)
    str_matrix = [join(string(matrix[i, j]) for j in 1:cols) for i in 1:rows]
    str_matrix = join(str_matrix, "\n")
    println(str_matrix)
end

# 示例矩阵
matrix = [1 2 3; 4 5 6; 7 8 9]

print_matrix(matrix)

123
456
789