Nixpkgs: AttributeError: 'NoneType' object has no attribute 'strip'

I want to add a vim plugin. Following the steps here, I have the error

[nix-shell:/home/rkochar/Projects/nixpkgs]# vim-plugins-updater
Traceback (most recent call last):
  File "/nix/store/p6vsfgajikjdlbspv37yaid1iv0l0w96-vim-plugins-updater-0.1/bin/..vim-plugins-updater-wrapped-wrapped", line 183, in <module>
    main()
  File "/nix/store/p6vsfgajikjdlbspv37yaid1iv0l0w96-vim-plugins-updater-0.1/bin/..vim-plugins-updater-wrapped-wrapped", line 179, in main
    editor.run()
  File "/nix/store/xibmvar7r9228dhpgl5bbzpq5r5n26s5-pluginupdate-py/pluginupdate.py", line 691, in run
    getattr(self, command)(args)
  File "/nix/store/p6vsfgajikjdlbspv37yaid1iv0l0w96-vim-plugins-updater-0.1/bin/..vim-plugins-updater-wrapped-wrapped", line 132, in update
    pluginupdate.update_plugins(self, args)
  File "/nix/store/xibmvar7r9228dhpgl5bbzpq5r5n26s5-pluginupdate-py/pluginupdate.py", line 929, in update_plugins
    update = editor.get_update(
             ^^^^^^^^^^^^^^^^^^
  File "/nix/store/xibmvar7r9228dhpgl5bbzpq5r5n26s5-pluginupdate-py/pluginupdate.py", line 500, in get_update
    current_plugin_specs = self.load_plugin_spec(config, input_file)
                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/nix/store/xibmvar7r9228dhpgl5bbzpq5r5n26s5-pluginupdate-py/pluginupdate.py", line 450, in load_plugin_spec
    return load_plugins_from_csv(config, plugin_file)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/nix/store/xibmvar7r9228dhpgl5bbzpq5r5n26s5-pluginupdate-py/pluginupdate.py", line 324, in load_plugins_from_csv
    plugin = PluginDesc.load_from_csv(config, line)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/nix/store/xibmvar7r9228dhpgl5bbzpq5r5n26s5-pluginupdate-py/pluginupdate.py", line 265, in load_from_csv
    repo = make_repo(row["repo"], branch.strip())
                                  ^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'strip'

I had a mistale in the ,, after writing the plugin name. Spotted it after taking a fresh look after a good night’s sleep.