Comment by pigcat

Here's my very simple solution

Add this to your ~/.zshrc or ~/.bashrc

alias alertme='printf \\a; sleep 0.1; printf \\a; sleep 0.1; printf \\a; sleep 0.1; printf \\a; sleep 0.1; printf \\a'

I add this after longish tasks - eg:

python longtest.py; alertme

seeddb; alertme