your CATPart will always have a PartBody. This is the main 'Container' for your solid. By default its name is "PartBody"
You can add many other "Bodies" which will define other 'containers' for 'not the main' solids.
you can switch any "Body" to the "PartBody", that will in the same time turn the current "PartBody" into a regular "Body" as you can have only one "PartBody".
You can not delete the "PartBody"
The "PartBody" does not have the "+" or "-" sign
I do not know if there is a way to check if the "PartBody" is the original one or a made up one (switch from Body to PartBody)
The properties of the Body/PartBody will give you date and time (HH:MM) of creation and modification, so you might compare this info with the creation date of the file. If time/hour is not the same then you know PartBody was made up, if time is the same, then you can't say.
Eric N.
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