new_contents: import threading
  import time
  from queue import Queue
  
  def job(l,q):
      for i in range(len(l)):
          l[i] = l[i]**2
      q.put(l)
  
  def multithreading():
      q = Queue()
      threads = []
      data = [[1,2,3],[3,4,5],[4,4,4],[5,5,5]]
      for i in range(4):
          t = threading.Thread(target=job, args=(data[i], q))
          t.start()
          threads.append(t)
      for thread in threads:
          thread.join()
      results = []
      for _ in range(4):
            results.append(q.get())
      print(results)
  
  if __name__ == '__main__':
      multithreading()
  
subject: create thread4