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+Photos (and iPhotos as well as Aperture) stores data about the photos in the Photos library in a sqlite3 database file inside the `Photos Library.photoslibrary` folder.
+
+osxphotos currently supports the following versions of the Photos database and associated MacOS version:
+* Photos 2.0 (MacOS 10.12)
+* Photos 3.0 (MacOS 10.13)
+* Photos 4.0 (MacOS 10.14)
+* Photos 5.0 (MacOS 10.15)
+
+In Photos 2.0 - 4.0, the database format is very similar between versions.  Photos 5.0 appeared to be a complete rewrite with a completely different database structure.
+
+In Photos 2.0 - 4.0, the sqlite3 database is located in:
+    `~/Pictures/Photos Library.photoslibrary/database/photos.db'
+