code: func Listen(repo distribution.Repository, remover distribution.RepositoryRemover, listener Listener) (distribution.Repository, distribution.RepositoryRemover) {
  	return &repositoryListener{
  			Repository: repo,
  			listener:   listener,
  		}, &removerListener{
  			RepositoryRemover: remover,
  			listener:          listener,
  		}
  }
docs: // Listen dispatches events on the repository to the listener.