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I have a server and client where multiple clients will be connecting to multiple server and does something. I want to make client connection to server async.

clients = [1,2,3] for c in clients: connect_to_server()

right now the above code connects to server but waits for first iteration to be executed and then second. how to make it async function call to connect_to_server() method so that second iteration will not wait for first to be executed ? And which function has to be async either connect_to_server or for loop function and which has to be awaiting ?

 def connect_to_server(client_id): print(client_id) time.sleep(3) async def main(): clients = [1, 2, 3, 4] for client in clients: await connect_to_server(client) asyncio.run(main())
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Here wrap the code you want to be async in an async function,

import asyncio async def main(): clients = [1,2,3] for c in clients: await connect_to_server() asyncio.run(main())

Explaination : here asyncio calls your async "MAIN" function and "AWAIT" in the function makes the process proceed to the next iteration without waiting for connect_to_server() function to finish !

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I tried the above and I get this error TypeError: object NoneType can't be used in 'await' expression
@VimalanE what does the connect_to_server function does ? Is it even defined or are you running this snippet as it is ?
I have updated the code for you in my question have a look
just for learning am printing the argument in connect_to_server which is not async function
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Your code will run at least for as much time is necessary to run the syncronous code. The following code illustrates this:

import asyncio import time async def connect_to_server(client_id): print(client_id) print(f'sleep for client_id {client_id}') time.sleep(1) print(f'async sleep for client_id {client_id}') await asyncio.sleep(1) print(f'done for client_id {client_id}') async def main(): clients = range(10) # Launch all of the coroutines in parallel coroutines = [connect_to_server(client) for client in clients] # Wait for all corountines to complete await asyncio.gather(*coroutines) start = time.time() asyncio.run(main()) print(f'Time elapsed: {time.time() - start} seconds')

The code above takes no less than 11 seconds to complete.

Beware! The following code calls await connect_to_server in a loop:

import asyncio import time async def connect_to_server(client_id): print(client_id) print(f'sleep for client_id {client_id}') time.sleep(1) print(f'async sleep for client_id {client_id}') await asyncio.sleep(1) print(f'done for client_id {client_id}') async def main(): clients = range(10) # Launch all of the coroutines in parallel for client in clients: await connect_to_server(client) start = time.time() asyncio.run(main()) print(f'Time elapsed: {time.time() - start} seconds')

The above code takes no less than 20 seconds to complete.

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