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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 set_input_by_id(self, _id, value):
 """ Set the value of form element by its `id` attribute. :param _id: id of element :param value: value which should be set to element """


        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()
        # pylint: disable=no-member
        return self.set_input(elem.get('name'), value)