如何在给定的文件中创建嵌套字典？

import json

def create_nested_dict(file_path):
    nested_dict = {}

    with open(file_path, 'r') as file:
        data = json.load(file)

    for key, value in data.items():
        keys = key.split('.')
        current_dict = nested_dict

        for k in keys[:-1]:
            if k not in current_dict:
                current_dict[k] = {}
            current_dict = current_dict[k]

        current_dict[keys[-1]] = value

    return nested_dict

# 示例文件内容：
# {
#   "person.name.first": "John",
#   "person.name.last": "Doe",
#   "person.age": 30
# }

file_path = 'example.json'
nested_dict = create_nested_dict(file_path)
print(nested_dict)

{
  "person": {
    "name": {
      "first": "John",
      "last": "Doe"
    },
    "age": 30
  }
}