@albanD unless you suspect that there’s something weird going on threading, there doesn’t appear to be a whole lot:
$ gdb python
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Reading symbols from python...done.
(gdb) run net_test.py
Starting program: /home/clemente/anaconda3/bin/python net_test.py
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/usr/lib/libthread_db.so.1".
[New Thread 0x7fffb7b78700 (LWP 18149)]
[New Thread 0x7fffb7377700 (LWP 18150)]
[New Thread 0x7fffb6b76700 (LWP 18151)]
done
^C
Thread 1 "python" received signal SIGINT, Interrupt.
0x00007ffff76c4299 in pthread_cond_destroy@@GLIBC_2.3.2 () from /usr/lib/libpthread.so.0

but I’d be interested as to why this is happening to me and not anyone else…