def set_input_by_id(self, _id, value):

        xpath = './/*[@id="%s"]' % _id
        if self._lxml_form is None:
            self.choose_form_by_element(xpath)
        sel = XpathSelector(self.form)
        elem = sel.select(xpath).node()
        return self.set_input(elem.get('name'), value)
Set the value of form element by its `id` attribute.
dataset/ETHPy150Open lorien/grab/grab/document.py/FormExtension.set_input_by_id