Unknown command: `repo-art` Cocoapods

I have installed the Cocoapods-art in the bundle using this command:

 bundle exec gem install cocoapods-art

This is the success message:

Fetching cocoapods-art-1.0.4.gemSuccessfully installed cocoapods-art-1.0.4Parsing documentation for cocoapods-art-1.0.4Done installing documentation for cocoapods-art after 0 seconds1 gem installed

when I execute: bundle exec gem list, I don't see Cocoapods repo-art in the gem list.

When I try to add: pod repo-art add folderNamer, I get:

 [!] Unknown command: `repo-art`Did you mean: repo?