Good morning 🙂 I'm quite new in prefect and I would like an advice for a problem that I have. In the example below all numbers (the list) have to be processed before saving the number (save_number()). I would like to know how I can process one number per time. For the first number in the list i execute the whole flow, for the second number i execute the whole flow, and so on ... This is an simple example, I'm thinking more if i have to process a lot of data. Many Thanks

from prefect import Flow, task
import prefect

import time

from prefect.executors import LocalDaskExecutor


logger = prefect.context.get("logger")


@task
def add_ten(x):
    time.sleep(1)
    return x + 10


@task
def save_number(y):
    <http://logger.info|logger.info>(f"Saving number: {y}")


with Flow("reduce", executor=LocalDaskExecutor()) as flow:
    mapped_result = add_ten.map([1, 2, 3, 4, 5, 6, 7, 8, 9, 9])
    mapped_result_2 = add_ten.map(mapped_result)
    reduced_result = save_number(mapped_result_2)

So mapping in general is designed to run things in parallel, but if you use the default LocalExecutor instead of LocalDaskExecutor, then everything will run sequentially.

with Flow("reduce", executor=LocalExecutor()) as flow:

@Anna Geller humm many thanks for your answer. I have tested the example here and worked. 🙇 and probably i have a bug in my project also :ladybug: