python_concurrent

import concurrent.futures

def do(params):
    return "hello"

with concurrent.futures.ThreadPoolExecutor(max_workers=5) as executor:
    future = executor.submit(do, params)
    
    for future in concurrent.futures.as_completed(future_to_url):
        url = future_to_url[future]
        try:
            data = future.result()
        except Exception as exc:
            print('%r generated an exception: %s' % (url, exc))
        else:
            print('%r page is %d bytes' % (url, len(data)))