[Python] How to keep the original order of input when using ThreadPoolExecutor?

from concurrent.futures import ThreadPoolExecutor, as_completed

def add_one(number, n):
return number + 1 + n

def process():
all_numbers = []
for i in range(0, 10):
all_numbers.append(i)

threads = []
all_results = []
with ThreadPoolExecutor(max_workers=10) as executor:
for number in all_numbers:
threads.append(executor.submit(add_one, number))

for index, task in enumerate(as_completed(threads)):
result = task.result()
#print(result)
all_results.append(result)

for index, result in enumerate(all_results):
print(result)

process()


If I set max_works=1, it will print out from 1 to 10 in order; if I set max_workers = 10, the order could be random:

5
3
10
7
1
8
6
2
4
9


How to keep the original order of the input when using ThreadPoolExecutor to process a list of items as in this example?

Continue reading...