code: func (s *AccessService) GetRole(name string) (services.Role, error) {
  	if name == "" {
  		return nil, trace.BadParameter("missing role name")
  	}
  	item, err := s.Get(context.TODO(), backend.Key(rolesPrefix, name, paramsPrefix))
  	if err != nil {
  		if trace.IsNotFound(err) {
  			return nil, trace.NotFound("role %v is not found", name)
  		}
  		return nil, trace.Wrap(err)
  	}
  	return services.GetRoleMarshaler().UnmarshalRole(item.Value,
  		services.WithResourceID(item.ID), services.WithExpires(item.Expires))
  }
docs: // GetRole returns a role by name