odoo-survey-addons/survey_select_input/models/survey_user_input.py

from odoo import models, fields, api


class SurveyUserInput(models.Model):
    _inherit = 'survey.user_input'

    selected = fields.Boolean(string="Selected", default=False)

    @api.multi
    def toggle_selected(self):
        unselect = self.filtered('selected')
        unselect.write({'selected': False})
        (self - unselect).write({'selected': True})