$ ./python -m test -u all,-gui 
(...)
0:24:10 load avg: 0.92 [326/478] test_pyclbr
0:24:13 load avg: 0.92 [327/478] test_pyexpat
0:24:13 load avg: 0.92 [328/478] test_pyrepl

(gdb) where
#0  0x00007f3b0325ec37 in select () from /lib64/libc.so.6
#1  0x00007f3af40f4497 in Sleep (milli=<optimized out>) at ./Modules/_tkinter.c:371
#2  0x00007f3af40f4faa in EventHook () at ./Modules/_tkinter.c:3350
#3  0x0000000000666d86 in os__inputhook_impl (module=<optimized out>) at ./Modules/posixmodule.c:16795
#4  0x0000000000666dad in os__inputhook (module=<optimized out>, _unused_ignored=_unused_ignored@entry=0x0)
    at ./Modules/clinic/posixmodule.c.h:12134
(...)

(gdb) py-bt
Traceback (most recent call first):
  <built-in method _inputhook of module object at remote 0x7f3af53d9850>
  File "/home/vstinner/python/main/Lib/_pyrepl/reader.py", line 719, in handle1
    input_hook()
  File "/home/vstinner/python/main/Lib/test/test_pyrepl/support.py", line 75, in handle_all_events
    reader.handle1()
  File "/home/vstinner/python/main/Lib/test/test_pyrepl/test_unix_console.py", line 197, in test_cursor_back_write
    _, con = handle_events_unix_console(events)
  File "/home/vstinner/python/main/Lib/unittest/mock.py", line 1423, in patched
    return func(*newargs, **newkeywargs)
  File "/home/vstinner/python/main/Lib/unittest/case.py", line 606, in _callTestMethod
    result = method()
  File "/home/vstinner/python/main/Lib/unittest/case.py", line 660, in run
    self._callTestMethod(testMethod)
(...)