[Python] Using a semaphore with asyncio in Python

I am trying to limit the number of simultaneous async functions running using a semaphore, but I cannot get it to work. My code boils down to this:

import asyncio


async def send(i):

print(f"starting {i}")
await asyncio.sleep(4)
print(f"ending {i}")


async def helper():
async with asyncio.Semaphore(value=5):
await asyncio.gather(*[
send(1),
send(2),
send(3),
send(4),
send(5),
send(6),
send(7),
send(8),
send(9),
send(10),
])


if __name__ == "__main__":
loop = asyncio.get_event_loop()
loop.run_until_complete(helper())
loop.close()


The output is:

starting 1
starting 2
starting 3
starting 4
starting 5
starting 6
starting 7
starting 8
starting 9
starting 10
ending 1
ending 2
ending 3
ending 4
ending 5
ending 6
ending 7
ending 8
ending 9
ending 10


I hope and expect that only 5 will run at time, however all 10 start and stop at the same time. What am I doing wrong?

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