how to fix the store after using rm to remove packages

[Myles English]

Hello, I had a problem with a python application and deleted (with rm,
instead of 'guix package -r') the packages I wanted to rebuild.

Now the store is broken.  I have just started down the guix road so
don't mind starting again with a clean store.  Or I could try and fix
the problem.  I haven't found any information on how to start again, but
have tried fixing it and have got stuck on how to delete derivations.
Can anyone help please?

» guix gc --verify     
reading the Nix store...
checking path existence...
path `/gnu/store/h242pz6byqng0sba9ka18kzyir9jwrvp-uwsgi-2.0.12.drv' 
disappeared, but it still has valid referrers!
path `/gnu/store/42bgmfv99vz60rpz6mvg24d770ncy9mn-uwsgi-2.0.12.drv' 
disappeared, removing from database...
guix gc: error: build failed: invalidating path 
`/gnu/store/42bgmfv99vz60rpz6mvg24d770ncy9mn-uwsgi-2.0.12.drv' in database: 
FOREIGN KEY constraint failed

» guix gc --referrers 
/gnu/store/h242pz6byqng0sba9ka18kzyir9jwrvp-uwsgi-2.0.12.drv
/gnu/store/4agl5ans64cczi952i92lv1s2hbz26jq-info-dir.drv
/gnu/store/98pfcxxbql67z4ynj6pp2fjxd42fmi5p-profile.drv
/gnu/store/dm45nh1nmzykd4fk43kp7jacqi6qm3gq-profile.drv
/gnu/store/g254pmk9a77bc3qkxylzhc722941zjqq-profile.drv
/gnu/store/gvg34dd5qd2dlkv7r0hzs852nk1jz0xh-ca-certificate-bundle.drv
/gnu/store/ijngd7ba9r2qj6ljrpg47byvx8wnkrvc-ca-certificate-bundle.drv
/gnu/store/mgx29vmfcsb6f8zwjy7q11czgc1ink61-info-dir.drv
/gnu/store/mkfjlghkn1wyh1fs27h4wysap8b70sii-info-dir.drv
/gnu/store/qv5lzfqmka7hffil9x1pm76sp6jc3bkq-profile.drv
/gnu/store/vcijdim5drgqghkcfcivpxvz206ld1vz-ca-certificate-bundle.drv
/gnu/store/w9fmqqvw4zg3c2gfpc0n3mkrwdfmv51c-info-dir.drv
/gnu/store/zd4mswmji4a4rcnc0w1ijxv7p983ahzy-ca-certificate-bundle.dr

» guix package --list-generations 
Generation 7    May 17 2016 10:52:09    (current)
  glibc-locales 2.22    out     
/gnu/store/dcqdfyal290awy1lwb6sxzs8sg0wr99h-glibc-locales-2.22
  guix  0.9.0-1.dd21    out     
/gnu/store/ya2rz4fbfismzbvygrc19ihwc0yiy5xy-guix-0.9.0-1.dd21
  ghc   7.10.2  out     /gnu/store/c0d4na71mdxkw9p42z9paj88x00ng1q4-ghc-7.10.2

Thanks,
Myles