title: python thread.join() not join to caller thread but to another assigned thread?
body: <p>python code:</p>
  
  <pre><code>import threading
  
  def f1():
      #long looping
  
  def f2():
      #another long looping  
  
  t1 = threading.Thread(target=f1)
  t2 = threading.Thread(target=f2)
  
  t1.start()
  t2.start()   
  
  #t2.join(t1) &lt;---???
  </code></pre>
  
  <p>Is that possible in main thread to call something like <code>t2.join(t1)</code>?
  Understanding that I can call <code>t2.join()</code> from <code>f1()</code>, but I am seeking an way calling from external(not in t1 and t2).</p>
  
  <p>Thank you.</p>