Modifying body of select message in a 'mbox' file.

[Michael March]

I am been playing with the 'email' and 'mailbox' modules trying to read
in an email at a time from an mbox file, add something to the body of a
message and then write that change back out in 'mbox' format again.

Is there any code floating around out there that allows you to take a
message from 'mailbox', modify it with 'email' and then write it back
out via 'mailbox' again?

thanks!