/usr/share/psi/plugin/ is in psi4-data 1:0.3-5.
This file is owned by root:root, with mode 0o755.
..
/usr/share/psi/plugin/CMakeLists.txt.template
/usr/share/psi/plugin/Makefile.template
/usr/share/psi/plugin/__init__.py.template
/usr/share/psi/plugin/aointegrals.cc.template
/usr/share/psi/plugin/doc.rst.template
/usr/share/psi/plugin/input.dat.template
/usr/share/psi/plugin/mointegrals.cc.template
/usr/share/psi/plugin/plugin.cc.template
/usr/share/psi/plugin/pymodule.py.template
/usr/share/psi/plugin/scf.cc.template
/usr/share/psi/plugin/scf.pymodule.py.template
/usr/share/psi/plugin/scf.scf.cc.template
/usr/share/psi/plugin/scf.scf.h.template
/usr/share/psi/plugin/sointegrals.cc.template
/usr/share/psi/plugin/wavefunction.cc.template