how: embed + extend to control my running app?

[David M. Cotter]

i'd like my app to be "available" to python while it's running.

for example, say my app is "FooBar.app".

when my FooBar.app is running, now there is a python interface available to python, and the user can write python scripts to make use of it.

with their scripts, they can control my running application

when FooBar.app is NOT running, perhaps making use of any of the python functions of "FooBar.app" would either return an error, or possibly launch "FooBar.app"?  or do nothing since it's not running?

can boost::python help with this?

i've never worked with extending or embedding python, so any help would be super great