anchor.diff:  
       if erlang:length(Hosts) >= 2 ->
               {Hosts, UserName, undefined};
  -        true -> 
  +        true ->
               erlang:error(not_enough_nodes)
       end.
   
  
positive.code:                         end
                  end
          end, Flatten),
      info("Bench final metrics: ~p", [Res], State),
      Res.
  
  statistics([], _) -> [];
  
negative.code:     end.
  
  run_periodically(StartTime, MaxTime, RetryTimeoutSec, Fn) ->
      case Fn() of
          ok -> ok;
          retry ->
              TimeSinceStart = seconds() -  StartTime,
  