def checkUser(self, rows, userId, request):
session = request.getSession()
_ = session._
d = defer.maybeDeferred(lambda: None)
if len(rows) != 1:
d.addCallback(lambda a: \
request.write(self.template.unexpectedArguments(session, \
_('No es alumno del cliente'))))
else:
erase = DBDelete(self.db)
to_delete = str(rows[0][0])
d.addCallback(lambda a: erase.deletePupil(to_delete))
d.addCallback(lambda a: request.write('<div class="message">' + \
_('El usuario ha sido borrado correctamente') + '</div>'))
return d
