from odoo import api, fields, models class HrEmployee(models.Model): _inherit = "hr.employee" count_courses = fields.Integer( "Number of courses", compute="_compute_count_courses" ) courses_ids = fields.One2many( "hr.course.attendee", "employee_id", string="Courses", readonly=True, ) @api.depends("courses_ids") def _compute_count_courses(self): for r in self: r.count_courses = len(r.courses_ids) def action_view_course(self): action = self.env.ref("hr_course.action_view_course") result = action.read()[0] result["domain"] = [("employee_id", "=", self.id)] return result