给定一组学生分数，编写一个Python脚本来计算分数的平均值和标准差。


学生分数的列表，例如：[78, 92, 85, 67, 88]
```python
import statistics

scores = [78, 92, 85, 67, 88]
mean = statistics.mean(scores)
stdev = statistics.stdev(scores)

print("Mean score is:", mean)
print("Standard deviation is:", stdev)
```
输出：
```
Mean score is: 82
Standard deviation is: 9.257741528707706
```