Asynchronous method call in Python without creating threads or forking process?

Question

Some years ago, (for comparison) synchronous JavaScript ajax requests were deprecated because of the overhead.
I’m in the following situation :

def ssh_network_operation_with_paramiko(string):
    server_response=Do_some_stuff_with_null_characters_in_string(string)
    Do_something_with_server_response(server_response)

for i in very_very_large_range
    ssh_network_operation_with_paramiko(i)

Basically, using process or threads would be synonym of creating a fork bomb.

So is it possible to do perform asynchronous calls without creating threads or process like with ajax in JavaScript ? Because all I found currently involve creating threads or process were each of them perform only one function at time.