Python multiple threads - how to join

from threading import Thread, active_count, current_thread
import time

def fun(val):
  for _ in range(5):
    print(val, current_thread())
    time.sleep(3)

threads = []
for i in range(1, 11):
   t = Thread(target=fun, args=(i*i,))
   threads.append(t)
   t.start()
   print("Current Threads count: %i." % active_count())

#Join threads
for t in threads:
    t.join()

print('bye')


Output:
######
1 <Thread(Thread-1, started 140645849839360)>
Current Threads count: 2.
4 <Thread(Thread-2, started 140645841446656)>
Current Threads count: 3.
9 <Thread(Thread-3, started 140645833053952)>
Current Threads count: 4.
16 <Thread(Thread-4, started 140645616318208)>
Current Threads count: 5.
25 <Thread(Thread-5, started 140645607925504)>
Current Threads count: 6.
36 <Thread(Thread-6, started 140645599532800)>
Current Threads count: 7.
49 <Thread(Thread-7, started 140645591140096)>
Current Threads count: 8.
64 <Thread(Thread-8, started 140645582747392)>
Current Threads count: 9.
81 <Thread(Thread-9, started 140645574354688)>
Current Threads count: 10.
100 <Thread(Thread-10, started 140645565961984)>
Current Threads count: 11.
4 <Thread(Thread-2, started 140645841446656)>
9 <Thread(Thread-3, started 140645833053952)>
16 <Thread(Thread-4, started 140645616318208)>
1 <Thread(Thread-1, started 140645849839360)>
100 <Thread(Thread-10, started 140645565961984)>
25 <Thread(Thread-5, started 140645607925504)>
36 <Thread(Thread-6, started 140645599532800)>
64 <Thread(Thread-8, started 140645582747392)>
49 <Thread(Thread-7, started 140645591140096)>
81 <Thread(Thread-9, started 140645574354688)>
4 <Thread(Thread-2, started 140645841446656)>
9 <Thread(Thread-3, started 140645833053952)>
16 <Thread(Thread-4, started 140645616318208)>
1 <Thread(Thread-1, started 140645849839360)>
100 <Thread(Thread-10, started 140645565961984)>
25 <Thread(Thread-5, started 140645607925504)>
36 <Thread(Thread-6, started 140645599532800)>
64 <Thread(Thread-8, started 140645582747392)>
81 <Thread(Thread-9, started 140645574354688)>
49 <Thread(Thread-7, started 140645591140096)>
4 <Thread(Thread-2, started 140645841446656)>
9 <Thread(Thread-3, started 140645833053952)>
16 <Thread(Thread-4, started 140645616318208)>
100 <Thread(Thread-10, started 140645565961984)>
1 <Thread(Thread-1, started 140645849839360)>
25 <Thread(Thread-5, started 140645607925504)>
36 <Thread(Thread-6, started 140645599532800)>
64 <Thread(Thread-8, started 140645582747392)>
81 <Thread(Thread-9, started 140645574354688)>
49 <Thread(Thread-7, started 140645591140096)>
4 <Thread(Thread-2, started 140645841446656)>
16 <Thread(Thread-4, started 140645616318208)>
9 <Thread(Thread-3, started 140645833053952)>
1 <Thread(Thread-1, started 140645849839360)>
100 <Thread(Thread-10, started 140645565961984)>
64 <Thread(Thread-8, started 140645582747392)>
25 <Thread(Thread-5, started 140645607925504)>
36 <Thread(Thread-6, started 140645599532800)>
81 <Thread(Thread-9, started 140645574354688)>
49 <Thread(Thread-7, started 140645591140096)>
bye