from concurrent.futures import threadpoolexecutor import time  # function simulating a task def task(n):     print(f"task {n} started")     time.sleep(2)  # simulates a long-running task     print(f"task {n} finished")     return f"result of task {n}"  # using threadpoolexecutor def execute_tasks():     tasks = [1, 2, 3, 4, 5]  # list of tasks     results = []      # create a thread pool with 3 simultaneous threads     with threadpoolexecutor(max_workers=3) as executor:         # execute tasks in parallel         results = executor.map(task, tasks)      return list(results)  if __name__ == "__main__":     results = execute_tasks()     print("all results:", results) 

task 1 started task 2 started task 3 started task 1 finished task 4 started task 2 finished task 5 started task 3 finished task 4 finished task 5 finished all results: ['result of task 1', 'result of task 2', 'result of task 3', 'result of task 4', 'result of task 5'] 

import requests from concurrent.futures import ThreadPoolExecutor  # Function to fetch a URL def fetch_url(url):     try:         response = requests.get(url)         return f"URL: {url}, Status: {response.status_code}"     except Exception as e:         return f"URL: {url}, Error: {e}"  # List of URLs to fetch urls = [     "https://example.com",     "https://httpbin.org/get",     "https://jsonplaceholder.typicode.com/posts",     "https://invalid-url.com" ]  def fetch_all_urls(urls):     with ThreadPoolExecutor(max_workers=4) as executor:         results = executor.map(fetch_url, urls)     return list(results)  if __name__ == "__main__":     results = fetch_all_urls(urls)     for result in results:         print(result)