Present on Debian, but not Ubuntu:
$ rma libcpupower-dev libcpupower-dev | 4.9.228-1 | oldstable | amd64, arm64, armel, armhf, i386, mips, mips64el, mipsel, ppc64el, s390x libcpupower-dev | 4.19.118-2+deb10u1~bpo9+1 | stretch-backports | amd64, arm64, armel, armhf, i386, mips, mips64el, mipsel, ppc64el, s390x libcpupower-dev | 4.19.132-1 | stable | amd64, arm64, armel, armhf, i386, mips, mips64el, mipsel, ppc64el, s390x libcpupower-dev | 5.7.10-1~bpo10+1 | buster-backports | amd64, arm64, armel, armhf, i386, mips, mips64el, mipsel, ppc64el, s390x libcpupower-dev | 5.7.10-1 | testing | amd64, arm64, armel, armhf, i386, mips64el, mipsel, ppc64el, s390x libcpupower-dev | 5.7.10-1 | unstable | amd64, arm64, armel, armhf, i386, mips64el, mipsel, ppc64el, s390x
Present on Debian, but not Ubuntu:
$ rma libcpupower-dev 2+deb10u1~ bpo9+1 | stretch-backports | amd64, arm64, armel, armhf, i386, mips, mips64el, mipsel, ppc64el, s390x
libcpupower-dev | 4.9.228-1 | oldstable | amd64, arm64, armel, armhf, i386, mips, mips64el, mipsel, ppc64el, s390x
libcpupower-dev | 4.19.118-
libcpupower-dev | 4.19.132-1 | stable | amd64, arm64, armel, armhf, i386, mips, mips64el, mipsel, ppc64el, s390x
libcpupower-dev | 5.7.10-1~bpo10+1 | buster-backports | amd64, arm64, armel, armhf, i386, mips, mips64el, mipsel, ppc64el, s390x
libcpupower-dev | 5.7.10-1 | testing | amd64, arm64, armel, armhf, i386, mips64el, mipsel, ppc64el, s390x
libcpupower-dev | 5.7.10-1 | unstable | amd64, arm64, armel, armhf, i386, mips64el, mipsel, ppc64el, s390x