code: func configureAuth(username, password, remoteURL string) (auth.CredentialStore, error) {
  	creds := map[string]userpass{}
  
  	authURLs, err := getAuthURLs(remoteURL)
  	if err != nil {
  		return nil, err
  	}
  
  	for _, url := range authURLs {
  		context.GetLogger(context.Background()).Infof("Discovered token authentication URL: %s", url)
  		creds[url] = userpass{
  			username: username,
  			password: password,
  		}
  	}
  
  	return credentials{creds: creds}, nil
  }
docs: // configureAuth stores credentials for challenge responses