$ ./python -m test test__interpchannels -R 3:3 -m test_send_buffer_blocking_waiting
...
test__interpchannels leaked [2, 2, 2] references, sum=6
...

$ ./python -m test test_interpreters -R 3:3 -m test_from_subinterpreter
...
test_interpreters leaked [11, 11, 11] references, sum=33
test_interpreters leaked [9, 9, 9] memory blocks, sum=27
...