Combine awaitables like Promise.all

by

The equivalent would be using asyncio.gather:

import asyncio

async def bar(i):
  print('started', i)
  await asyncio.sleep(1)
  print('finished', i)

async def main():
  await asyncio.gather(*[bar(i) for i in range(10)])

loop = asyncio.get_event_loop()
loop.run_until_complete(main())
loop.close()

Why doesn’t my approach work?

Because when you await each item in seq, you block that coroutine. So in essence, you have synchronous code masquerading as async. If you really wanted to, you could implement your own version of asyncio.gather using loop.create_task or asyncio.ensure_future.

EDIT

The original answer used the lower-level asyncio.wait.

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