Package: src:tumgreyspf Version: 1.36-4.1 Severity: important Python2.7 will go out of upstream security support during the Bullseye development cycle. It is not safe to assume it will be included in the next release, so if you want to be sure tumgreyspf can stay in Debian, please port it to python3.
Alternately, it's close to 8 years without a new release and there are certainly alternatives for SPF checking and greylisting. Removal might be in order. Personally, I want to remove some packages I maintain, particularly python- ipaddr, which tumgreyspf depends on (indirectly via python-spf - which I will change to python3 only) during the Bullseye cycle, regardless of what happens to python2.7, so please update (python3 includes the ipaddress module, which was developed from ipaddr, in the standard library).