How do proper cleanup/release resources when using luma.core?

[dachshund-digital]

How do proper cleanup/release resources when using luma.core? Using luma.core setting up SPI session, luma.core does not release resources? Sending SIGINT to instruct python based service (system-d) to stop, hangs sometimes, other times, returns quickly. Appears the SPI connection is not shutting down or cleaning up right? Have not found example of how to cleanup the luma.core session?

Setup....

from luma.led_matrix.device import max7219
from luma.core.interface.serial import spi, noop
from luma.core.virtual import sevensegment

ZERO=0
ONE=1
SERIAL=spi(port=ZERO, device=ZERO, gpio=noop())
DEVICE=max7219(SERIAL, cascaded=ONE)

theSegment=sevensegment(DEVICE)

But what to do for clean up?