使用迭代的方式有助于减少内存使用，看情况使用。

import time
import numpy
from itertools import islice

step = 30000
big_list = range(1000000)


# 方式一
t = time.time()
for new_list in numpy.array_split(big_list, round(len(big_list)/ step)):
    list(new_list)
print(new_list[-2])  # 测试结果
print(time.time() - t)

# 方式二
t = time.time()
def group_elements(lst, chunk_size):
    lst = iter(lst)
    return iter(lambda: tuple(islice(lst, chunk_size)), ())

for new_list in group_elements(big_list, step):
    list(new_list)
print(new_list[-2])  # 测试结果
print(time.time() - t)


# 方式三
t = time.time()
def split_list(lst, n):  
    for i in range(0, len(lst), n): 
        yield lst[i:i + n] 

for new_list in split_list(big_list, step):
    list(new_list)
print(new_list[-2])  # 测试结果
print(time.time() - t)


# 方式四
t = time.time()
for i in range(0, len(big_list), step):
    new_list = list(big_list[i:i + step])
print(new_list[-2])  # 测试结果
print(time.time() - t)

输出结果：

999998
0.21463561058044434
999998
0.03289985656738281
999998
0.047107696533203125
999998
0.022406339645385742

参考文章：
https://www.delftstack.com/howto/python/python-split-list-into-chunks/