function in an executable file that can be sourced or executed

[Mike McClain]

I have an executable file ~/bin/net that does the hocus pocus to bring
eth0 up and down. In another file, ~/bin/user.bash is a function, net(),
that does the same thing yet can be sourced.
Is there a way that I can put function net() in executable file ~/bin/net
with a call at the end like: [ if not sourced ] && net;
In other words, if ~/bin/net is called from the command line the
function will be executed?
Thanks,
Mike
--
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