I would like to set as a default value in a many2one the first value that my many2one has written and that the user does not see the many2one field without any value initially. Obviously, I would like the many2one field to show a default value for the user to be able to modify the value selected in the many2one if they wish. This is my code:

@api.model    
def default_location_ids_origin(self):
        for move_line in self:
            locations = self.env['stock.quant'].search([('product_id','=',move_line.product_id.id),('quantity','>',0.00),('on_hand','!=',False)],limit=1)
            return locations.location_id.id
location_ids_origin = fields.Many2one('stock.location',string='From',domain="[('id','in',location_id_products)]",default = default_location_ids_origin)