def add_permissions(self, group_name, resource, permissions, url_prefix, auth, session, send_opts):
        """
        Args:
            group_name (string): Name of group.
            resource (intern.resource.boss.BossResource): Identifies which data model object to operate on.
            permissions (list): List of permissions to add to the given resource.
            url_prefix (string): Protocol + host such as https://api.theboss.io
            auth (string): Token to send in the request header.
            session (requests.Session): HTTP session to use for request.
            send_opts (dictionary): Additional arguments to pass to session.send().
        """
        post_data = {"group": group_name,
                     "permissions": permissions,
                     }
        post_data.update(resource.get_dict_route())
        req = self.get_permission_request('POST', 'application/json',
                                          url_prefix, auth, post_data=post_data)
        prep = session.prepare_request(req)
        resp = session.send(prep, **send_opts)

        if resp.status_code != 201:
            msg = ('Failed adding permissions to group {}, got HTTP response: ({}) - {}'.format(group_name,
                                                                                                resp.status_code,
                                                                                                resp.text))
            raise HTTPError(msg, request=req, response=resp)