/usr/share/isenkram/Fw-Contents-powerpc-sid-contrib is in isenkram-cli 0.18+deb8u1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 | lib/firmware/prism2_ru.fw contrib/admin/prism2-usb-firmware-installer
lib/firmware/prism2_ru.hex contrib/admin/prism2-usb-firmware-installer
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