/usr/lib/python2.7/dist-packages/trytond/modules/product/uom.py is in tryton-modules-product 2.2.2-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/python2.7/dist-packages/trytond/modules/product/../../../../../../share/pyshared/trytond/modules/product/uom.py