anchor.diff:  -include_lib("eunit/include/eunit.hrl").
   -import(ring, [start/2, spawn_node/0, send_message/3, fetch_message/1]).
   
  -start_n_nodes_test() ->
  +start_ring_n_nodes_test() ->
       N = 3,
       M = initial_message,
   
  
positive.code:     Reply = fetch_message(NodePid2),
      ?assertEqual({Message, NodePid}, Reply).
  
  node_send_quit_message_to_recv_node_then_recv_node_die_test() ->
      NodePid = spawn_node(),
      NodePid2 = spawn_node(),
  
  
negative.code:     receive after 50 -> ok end,
      ?assertNot(is_process_alive(NodePid2)).
  
  send_message_around_the_ring_test() ->
      Message = initial_message,
      N = 3,
      Nodes = start(N, Message),
  