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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 search(self, id_ugroup):
 """Search Group User by its identifier. :param id_ugroup: Identifier of the Group User. Integer value and greater than zero. :return: Following dictionary: :: {‘user_group’: {'escrita': < escrita >, 'nome': < nome >, 'exclusao': < exclusao >, 'edicao': < edicao >, 'id': < id >, 'leitura': < leitura >}} :raise InvalidParameterError: Group User identifier is none or invalid. :raise GrupoUsuarioNaoExisteError: Group User not registered. :raise DataBaseError: Networkapi failed to access the database. :raise XMLError: Networkapi failed to generate the XML response. """


        if not is_valid_int_param(id_ugroup):
            raise InvalidParameterError(
                u'The identifier of Group User is invalid or was not informed.')

        url = 'ugroup/get/' + str(id_ugroup) + '/'

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

        return self.response(code, xml)