A diamond-shaped Prefect flow using mapping

example_diamond_flow.py

from prefect import task, Flow
import datetime
import random


@task
def inc(x):
    return x + 1


@task
def dec(x):
    return x - 1


@task
def add(x, y):
    return x + y


@task
def list_sum(arr):
    return sum(arr)


with Flow("dask-example") as flow:
    incs = inc.map(x=range(100))
    decs = dec.map(x=range(100))
    adds = add.map(x=incs, y=decs)
    total = list_sum(adds)