in usb_monitor_pkg/usb_monitor_pkg/mount_point_tracker.py [0:0]
def add_post_action(self, post_action):
"""Add a function to be executed on decrementing the reference to the mount point.
Args:
post_action (function): Function type to be added to the post_action list.
"""
if (post_action is not None) and (post_action not in self.post_action):
self.post_action.append(post_action)