data.json
[{"need_key": {"pri": ["outpatient_visit_id", "inpatient_visit_id"], "sub": "visit_id"}, "match_rules": [{"pri": ["visit_datetime", "admit_datetime"], "sub": ["create_application_datetime"]}], "principal_table": ["tbl_reg_registrations", "tbl_adt_admits_discharges"], "subordinate_table": "tbl_std_studies", "need_yidu_vid": "yes", "common_key": {"pri": "patient_id", "sub": "patient_id"}}]

如果你要处理的是文件而不是字符串，你可以使用 json.dump() 和 json.load() 来编码和解码JSON数据。例如：
#!/usr/bin/env python
# -*- coding: utf-8 -*-
import json
import os,sys

with open('data.json', 'r') as f:
    data = json.load(f)
    print(data[0]["need_yidu_vid"])

# Writing JSON data
with open('data.json', 'w') as f:
    json.dump(data, f)