写一个代码段，该代码段在 Python 中将一个数字列表中的所有元素加起来并计算该列表的平均值。
[10, 20, 30, 40, 50]
```
num_list = [10, 20, 30, 40, 50]
sum_num = sum(num_list)
avg_num = sum_num / len(num_list)

print("Sum of Numbers: ", sum_num)
print("Average of Numbers: ", avg_num)
```
输出:
```
Sum of Numbers: 150
Average of Numbers: 30.0
```