如何在Python中不加载到内存的情况下对大字典列表进行排序

import heapq
import tempfile
import os

def external_sort_large_dict_list(data, key):
    chunk_size = 10000  # 每个小块的大小
    chunks = []
    sorted_files = []

    # 分割大字典列表为小块
    for i in range(0, len(data), chunk_size):
        chunk = data[i:i+chunk_size]
        chunk.sort(key=key)
        chunks.append(chunk)

    # 将每个小块写入临时文件
    for i, chunk in enumerate(chunks):
        temp_file = tempfile.NamedTemporaryFile(delete=False)
        temp_file.writelines([f"{item}\n" for item in chunk])
        temp_file.close()
        sorted_files.append(temp_file.name)

    # 归并排序合并临时文件
    result = []
    with open(sorted_files[0], 'r') as file1:
        heap = []
        for line in file1:
            item = line.strip()
            heapq.heappush(heap, (key(item), item))

        for file_path in sorted_files[1:]:
            with open(file_path, 'r') as file:
                for line in file:
                    item = line.strip()
                    heapq.heappushpop(heap, (key(item), item))

        while heap:
            result.append(heapq.heappop(heap)[1])

    # 删除临时文件
    for file_path in sorted_files:
        os.remove(file_path)

    return result

data = [{'name': 'Alice', 'age': 25}, {'name': 'Bob', 'age': 30}, {'name': 'Charlie', 'age': 20}]
sorted_data = external_sort_large_dict_list(data, key=lambda x: x['age'])
print(sorted_data)