如何在数据未定义时有效地向嵌套json添加值

import json

# 假设有以下嵌套JSON数据
nested_json = '''
{
  "person": {
    "name": "John",
    "age": 30,
    "address": {
      "city": "New York",
      "country": "USA"
    }
  }
}
'''

# 将JSON字符串解析为字典对象
data = json.loads(nested_json)

# 检查要添加值的位置是否存在，如果不存在，则创建相应的嵌套结构
if 'person' not in data:
    data['person'] = {}
if 'address' not in data['person']:
    data['person']['address'] = {}

# 向嵌套JSON添加值
data['person']['address']['street'] = '123 Main St'

# 将更新后的对象转换回JSON字符串
updated_json = json.dumps(data)

print(updated_json)