多处理python程序包出现泡菜错误

Question

我正在尝试将非常简单的功能与多处理并行化

from multiprocessing import Pool
import time
import multiprocessing as mp
import numpy as np

def main():
    num_cpus = mp.cpu_count() - 1
    pool = mp.Pool(processes=num_cpus)
    data = list(range(0,20))
    index_chunks = np.array_split(data, num_cpus)
    print(index_chunks)

    def f(x):
        return sum(x)

    data_list = [list(index_element) for index_element in index_chunks]
    async_mapper = pool.map_async(f, data_list)
    async_mapper.wait()
    pool.close()
    result_list = async_mapper.get()
    print(result_list)

if __name__ == '__main__':
    main()

我收到以下错误：

Traceback (most recent call last):
  File "C:/Users/user/Documents/Projects/folder/multiprocessing_test/test.py", line 24, in <module>
    main()
  File "C:/Users/user/Documents/Projects/folder/multiprocessing_test/test.py", line 20, in main
    result_list = async_mapper.get()
  File "C:\Users\user\AppData\Local\Continuum\anaconda3\lib\multiprocessing\pool.py", line 644, in get
    raise self._value
  File "C:\Users\user\AppData\Local\Continuum\anaconda3\lib\multiprocessing\pool.py", line 424, in _handle_tasks
    put(task)
  File "C:\Users\user\AppData\Local\Continuum\anaconda3\lib\multiprocessing\connection.py", line 206, in send
    self._send_bytes(_ForkingPickler.dumps(obj))
  File "C:\Users\user\AppData\Local\Continuum\anaconda3\lib\multiprocessing\reduction.py", line 51, in dumps
    cls(buf, protocol).dump(obj)
AttributeError: Can't pickle local object 'main.<locals>.f'

有人可以解释如何解决吗？我在Windows和Linux上都收到此错误，非常感谢！