Hi everyone, I wanna add a <separator string=""/> in my view but i have this error: Uncaught TypeError: object is not a function

any idea please

.py

enter code here'timetable_ids':fields.one2many('time.table.line', 'table_id', 'TimeTable'),

.xml

enter code here<notebook colspan="4">
                    <page string="TimeTable">
                        <field name="timetable_ids" nolabel="1" colspan="4">
                        <tree string="TimeTable" editable="bottom">
                            <field name="week_day"/>
                            <field name="demblc1"/>
                            <field name="teacher_id1" domain="[('job_id.name','=','prof')]"/> 
                             <separator string="Details des points de transport" colspan="4"/>