Selected row in one2many in Wizard


I have an one2many field in wizard.
When I execute the button action in wizard, how to select only selected row in one2many to select?
Currently, it only can select all the rows in the one2many field.

downloads_ids = fields.One2Many(“target.table”, None, "Target Field)

Example as the picture below, I wanted only Top First row to be execute.
Is it possible?

You can not because there are no selection on One2Many, row is there or not.
If you need to “select” rows, you must use a Many2Many and optionally you can use the multiselection widget.