如何打印JSON字符串的嵌套对象的值？

import json

def print_nested_values(json_obj):
    if isinstance(json_obj, dict):
        for key, value in json_obj.items():
            if isinstance(value, dict) or isinstance(value, list):
                print_nested_values(value)
            else:
                print(f"{key}: {value}")
    elif isinstance(json_obj, list):
        for item in json_obj:
            print_nested_values(item)

# 示例JSON字符串
json_str = '''
{
  "name": "John",
  "age": 30,
  "address": {
    "street": "123 Main St",
    "city": "New York"
  },
  "hobbies": ["reading", "traveling"]
}
'''

# 将JSON字符串解析为Python对象
json_obj = json.loads(json_str)

# 打印嵌套对象的值
print_nested_values(json_obj)

name: John
age: 30
street: 123 Main St
city: New York
reading
traveling