Most GNU packages do not have a Release part, but how this is modeled in a PSF is described here anyway.
The Release part is analogous to the RPMTAG_RELEASE
and debian_revision attributes, hence GNU software
releases do no have this part because GNU packages are the original 'upstream' releases relative to the packages of
GNU/Linux distributions.
The Name becomes the product.tag attribute. The Revision becomes the product.revision attribute. The Release becomes the product.vendor_tag attribute.