code: def add_permissions(self, group_name, resource, permissions, url_prefix, auth, session, send_opts):
          
          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)
docs: 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().