Merging data.

[James Russell Kuyper Jr.]

I've been sharing my Gnucash file with my wife via a USB thumb drive,
with each of us making changes to the file on our own computer using the
thumb drive, and with me periodically saving a copy to my hard disk.
Well, it was bound to happen, sooner or later: I accidentally made
changes to my hard disk copy at a time when it had not been updated to
include the changes my wife had recently made to the flash drive copy.
Is there any simple way to merge the two copies, so as to combine my own
changes with my wife's changes, without duplicating the records that
neither of us changed?