/usr/lib/python2.7/dist-packages/trytond/modules/product_cost_fifo/__tryton__.py is in tryton-modules-product-cost-fifo 2.2.0-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/python2.7/dist-packages/trytond/modules/product_cost_fifo/../../../../../../share/pyshared/trytond/modules/product_cost_fifo/__tryton__.py