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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def inserir(self, id_user, id_group):
 """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. """

        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)