code: def inserir(self, id_user, id_group):
          
          if not is_valid_int_param(id_user):
              raise InvalidParameterError(
                  u'The identifier of User is invalid or was not informed.')
  
          if not is_valid_int_param(id_group):
              raise InvalidParameterError(
                  u'The identifier of Group is invalid or was not informed.')
  
          url = 'usergroup/user/' + \
              str(id_user) + '/ugroup/' + str(id_group) + '/associate/'
  
          code, xml = self.submit(None, 'PUT', url)
docs: Create a relationship between User and Group.
  
          :param id_user: Identifier of the User. Integer value and greater than zero.
          :param id_group: Identifier of the Group. Integer value and greater than zero.
  
          :return: Dictionary with the following structure:
  
          ::
              {'user_group': {'id': < id_user_group >}}
  
          :raise InvalidParameterError: The identifier of User or Group is null and invalid.
          :raise GrupoUsuarioNaoExisteError: UserGroup not registered.
          :raise UsuarioNaoExisteError: User not registered.
          :raise UsuarioGrupoError: User already registered in the group.
          :raise DataBaseError: Networkapi failed to access the database.
          :raise XMLError: Networkapi failed to generate the XML response.