/usr/share/lintian/overrides/python3-gi is in python3-gi 3.20.0-0ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 | python3-gi: package-name-doesnt-match-sonames *
python3-gi: dev-pkg-without-shlib-symlink *
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