How can I replace the queue in this case with semaphore or mutex lock

Question

I have 4 thread that reading from 4 text files and additional thread to write that 4 threads already read , I used the Queue, So How I can use semaphore or mutex lock?

• Code Run with Queue:

  import queue
  import threading
  from datetime import datetime
  
  start_time = datetime.now()
  
  def print_text(q, filename):
      for line in open(filename, encoding="utf8"):
          q.put(line.strip())
      q.put('--end--')
  
  def print_result(q, count=0):
      while count:
          line = q.get()
          if line == '--end--':
              count -= 1
          else:
              print(line)
  
  if __name__ == "__main__":
      filenames = ['file_1.txt', 'file_2.txt', 'file_3.txt', 'file_4.txt']
      q = queue.Queue()
      threads = [threading.Thread(target=print_text, args=(q, filename)) for filename in filenames]
      threads.append( threading.Thread(target=print_result, args=(q, len(filenames))) )
      for thread in threads:
          thread.start()
      for thread in threads:
          thread.join()
  time_elapsed = datetime.now() - start_time
  print('Time elapsed (hh:mm:ss.ms) {}'.format(time_elapsed))
  

• My attempt to solved by Mutex Lock:

  import threading
  import time
  import random
  
  mutex = threading.Lock()
  class thread_one(threading.Thread):
      def run(self):
          global mutex
          print ("The first thread is now sleeping")
          time.sleep(random.randint(1, 5))
          print("First thread is finished")
          mutex.release()
  
  class thread_two(threading.Thread):
      def run(self):
          global mutex
          print ("The second thread is now sleeping")
          time.sleep(random.randint(1, 5))
          mutex.acquire()
          print("Second thread is finished")
  
  class thread_three(threading.Thread):
      def run(self):
          global mutex
          print ("The Three thread is now sleeping")
          time.sleep(random.randint(1, 5))
          mutex.acquire()
          print("Three thread is finished")
  
  class thread_four(threading.Thread):
      def run(self):
          global mutex
          print ("The Four thread is now sleeping")
          time.sleep(random.randint(1, 5))
          mutex.acquire()
          print("Four thread is finished")
  
  mutex.acquire()
  t1 = thread_one()
  t2 = thread_two()
  t3 = thread_three()
  t4 = thread_four()
  t1.start()
  t2.start()
  t3.start()
  t4.start()
  

Answer 1

import queue                    
import threading                

s = threading.Semaphore(5)
def print_text(s, q, filenames):
    with s:
        for line in open(filenames, encoding="utf8"):
            q.put(line.strip())
        q.put('--end--')

def print_result(q, count=0):   
    while count:                
        line = q.get()          
        if line == '--end--':   
            count -= 1          
        else:
            print(line)

if __name__ == "__main__":
    filenames = ['file_1.txt', 'file_2.txt', 'file_3.txt', 'file_4.txt']

    q = queue.Queue()    

    threads = [threading.Thread(target=print_text, args=(s, q, filename)) for filename in filenames]
    
    threads.append( threading.Thread(target=print_result, args=(q, len(filenames))) ) 

    for thread in threads:
        thread.start()
    
    for thread in threads:
        thread.join()