如何从json中提取所有变量名？

import json

def extract_variable_names(json_data):
    variable_names = set()

    def extract_names(data):
        if isinstance(data, dict):
            for key, value in data.items():
                variable_names.add(key)
                extract_names(value)
        elif isinstance(data, list):
            for item in data:
                extract_names(item)

    extract_names(json_data)
    return variable_names

# 示例JSON数据
json_data = '''
{
    "name": "John",
    "age": 30,
    "address": {
        "street": "123 Main St",
        "city": "New York"
    },
    "hobbies": ["reading", "music"]
}
'''

# 解析JSON数据
parsed_data = json.loads(json_data)

# 提取变量名
variables = extract_variable_names(parsed_data)

# 打印所有变量名
for variable in variables:
    print(variable)

name
age
address
street
city
hobbies