/usr/lib/R/site-library/ProtGenerics/INDEX is in r-bioc-protgenerics 1.10.0-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
| 1 2 | ProtGenerics            S4 generic functions for Bioconductor
                        proteomics infrastructure
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