guile-examples/json/guix-env/channels.scm

(list (channel
       (name 'guix)
       (url "https://git.savannah.gnu.org/git/guix.git")
       (commit
        "191a4ced8efb98d66d547a3ee6c7b027120c7071")
       (introduction
        (make-channel-introduction
         "9edb3f66fd807b096b48283debdcddccfea34bad"
         (openpgp-fingerprint
          "BBB0 2DDF 2CEA F6A8 0D1D  E643 A2A0 6DF2 A33A 54FA")))))