code: func NewDockerKeyring() DockerKeyring {
  	keyring := &lazyDockerKeyring{
  		Providers: make([]DockerConfigProvider, 0),
  	}
  
  	// TODO(mattmoor): iterating over the map is non-deterministic.  We should
  	// introduce the notion of priorities for conflict resolution.
  	for name, provider := range providers {
  		if provider.Enabled() {
  			glog.Infof("Registering credential provider: %v", name)
  			keyring.Providers = append(keyring.Providers, provider)
  		}
  	}
  
  	return keyring
  }
docs: // NewDockerKeyring creates a DockerKeyring to use for resolving credentials,
  // which lazily draws from the set of registered credential providers.