Below is an instruction that describes a task. Write a response that appropriately completes the request.

### Instruction:
What is the sum of Tujia population with the Zhangjiajie prefecture in Sangzhi county?

### Inputs:
table_name: table, columns: ['Province', 'Prefecture', 'County', 'Tujia Population', "% of China's Tujia Population"]

### Response:
SELECT SUM Tujia Population FROM table WHERE Prefecture = zhangjiajie AND County = sangzhi