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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 list_by_group(self, id_ugroup):
 """Search Administrative Permission by Group User by identifier. :param id_ugroup: Identifier of the Group User. Integer value and greater than zero. :return: Dictionary with the following structure: :: {'perms': [{'ugrupo': < ugrupo_id >, 'permission': { 'function' < function >, 'id': < id > }, 'id': < id >, 'escrita': < escrita >, :raise InvalidParameterError: Group User is null and invalid. :raise UGrupoNotFoundError: Group User not registered. :raise DataBaseError: Networkapi failed to access the database. :raise XMLError: Networkapi failed to generate the XML response. """


        if id_ugroup is None:
            raise InvalidParameterError(
                u'The identifier of Group User is invalid or was not informed.')

        url = 'aperms/group/' + str(id_ugroup) + '/'

        code, xml = self.submit(None, 'GET', url)

        return self.response(code, xml)