Possible to batch Copy "Title" to "Part"?

I have a large Classical music library. Created a "Part" tag. I want to copy the title of the track "Title" to "Part." For example:

BEFORE
Title: 1. Largo ----- Part: empty
Title: 2. Presto ----- Part: empty

AFTER
Title: 1. Largo ----- Part: 1. Largo
Title: 2. Presto ----- Part: 2. Presto

I can do this manually, but with a 2000 albums and multiple tracks, it will be very tedious.

I am no expert in Mp3Tag, but am ready to learn!

You could start with the FAQs: /t/967/1

Write the value from tag-field TITLE to the tag-field PART.

Action: Format value

Field : PART
Formatstring: %TITLE%

See also ...
http://help.mp3tag.de/options_format.html#format

DD.20170623.1300.CEST

ohrenkino and DetlevD - you are very gracious.

I was not even sure what i needed to search for in the FAQs.

The info was very clear and i am on my way.

MANY THANKS!!