/usr/lib/python2.7/dist-packages/trytond/modules/purchase_invoice_line_standalone/locale/es_ES.po is in tryton-modules-purchase-invoice-line-standalone 3.0.0-2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/python2.7/dist-packages/trytond/modules/purchase_invoice_line_standalone/locale/../../../../../../../share/pyshared/trytond/modules/purchase_invoice_line_standalone/locale/es_ES.po