I tried to set a default status value to "Draft" when creating a new record, but the status is always blank. If I set the status manually, it worked. Here is the my command. Am I missing something?

class custom_purchase(models.Model):
    _name = 'custom.purchase'

    name = fields.Char(string="Name")
    tanggal = fields.Date(string="Tanggal")
    status = fields.Selection([('draft','Draft'),('approve','Approve'),('done','Done')], default='draft')