python3Packages.discogs-client: rename from discogs_client

pkgs/top-level/python-aliases.nix

@@ -37,8 +37,9 @@ mapAliases ({
   bugseverywhere = throw "bugseverywhere has been removed: Abandoned by upstream."; # Added 2019-11-27
   dateutil = python-dateutil; # added 2021-07-03
   detox = throw "detox is no longer maintained, and was broken since may 2019"; # added 2020-07-04
-  diff_cover = diff-cover; # added 2021-07-02
   dftfit = throw "it's dependency lammps-cython no longer builds";
+  diff_cover = diff-cover; # added 2021-07-02
+  discogs_client = discogs-client; # added 2021-07-02
   dns = dnspython; # Alias for compatibility, 2017-12-10
   faulthandler = throw "faulthandler is built into ${python.executable}";
   gitdb2 = throw "gitdb2 has been deprecated, use gitdb instead."; # added 2020-03-14

pkgs/top-level/python-packages.nix

@@ -1937,7 +1937,7 @@ in {
 
   discid = callPackage ../development/python-modules/discid { };
 
-  discogs_client = callPackage ../development/python-modules/discogs_client { };
+  discogs-client = callPackage ../development/python-modules/discogs-client { };
 
   discordpy = callPackage ../development/python-modules/discordpy { };