利用递归实现JSON字典的嵌套和扁平化

def flatten_json(json_dict, parent_key='', flattened_dict={}):
    for key, value in json_dict.items():
        new_key = parent_key + '.' + key if parent_key else key
        if isinstance(value, dict):
            flatten_json(value, new_key, flattened_dict)
        else:
            flattened_dict[new_key] = value
    return flattened_dict

def nest_json(flattened_dict):
    nested_dict = {}
    for key, value in flattened_dict.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