docs: def _update_session_count(self, type=0, actutal_session_count=0):
          ''' update the session/ascp count
              0 : set the number of sessions being used to 1 or number specified in transfer config
              -1: decrement the session count by one
               1: set the session count to param value
          '''
          if type == 0:  # init
              _count = 0
              if self._args.transfer_config:
                  _count = self._args.transfer_config.multi_session
              self._session_count = _count if _count > 0 else 1
          elif type == -1:  # decrement
              self._session_count -= 1
          elif type == 1:  # set from number of actual session objects
              self._session_count = actutal_session_count