I don't know about a Python library or json converter. But MarcEdit can do it.
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From: Code for Libraries <[log in to unmask]> On Behalf Of Goodwin, Shawn
Sent: Monday, March 4, 2019 3:03 PM
To: [log in to unmask]
Subject: [CODE4LIB] MARC21 to MODS
I was looking at this website: https://www.loc.gov/standards/mods/mods-mapping.html#mapping
Is there a python library (or even just a JSON file) that transforms MARC to MODS?
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