code: def grant_admin_role(self):
      
      apiuser = ApiUser(self._get_resource_root(), self.name, roles=['ROLE_ADMIN'])
      return self._put('', ApiUser, data=apiuser)
docs: Grant admin access to a user. If the user already has admin access, this
      does nothing. If the user currently has a non-admin role, it will be replaced
      with the admin role.
  
      @return: An ApiUser object