Can I write a script to take an action right before the computer is going to go to sleep?

I think my computer is randomly not syncing email correctly with Apple Mail, but it's only a problem when it wakes from sleep.

That issue is neither here nor there. What I'd like to do is write a script / something that will quit Apple Mail if it detects that the computer is going to sleep.

Ideally, there'd be a similar process to open Apple Mail upon waking from sleep, but that's less of an issue.

I tried looking for a system event library of some kind, but all I can find is fsevents (which I don't think has anything about sleep).

Thanks!