'Get specific notification recipient values to store on the notification
mail_mail. Basic method just set the recipient partners as mail_mail
recipients. Inherit this method to add custom behavior like using
recipient email_to to bypass the recipint_ids heuristics in the
mail sending mechanism.'

@api.multi
def message_get_recipient_values(self, notif_message=None, recipient_ids=None):

    return {'recipient_ids': [(4, pid) for pid in recipient_ids]}
