anchor.diff:  -spec freshen_specs(escalus:config(), [escalus_users:resource_spec()]) -> R when
         R :: [escalus_users:user_spec()].
   freshen_specs(Config, UserSpecs) ->
  -    Suffix = fresh_suffix(),
  +    Suffix = fresh_suffix(Config),
       lists:map(fun({_UserName, Spec}) -> Spec end,
                 freshen_specs(Config, UserSpecs, Suffix)).
   
  
positive.code:     lists:filter(fun({Name, _}) -> lists:member(Name, UserNames) end,
                   FullSpecs).
  
  fresh_suffix() ->
      {_, S, US} = erlang:now(),
      L = lists:flatten([integer_to_list(S rem 100), ".", integer_to_list(US)]),
      list_to_binary(L).
  
  
  tag(L) -> lists:zip(lists:seq(1, length(L)), L).
  untag(L) -> [ {Val, Error} || {_Ord, Val, Error} <- lists:sort(L) ].
  
negative.code: %% The side effect is the creation of XMPP users on a server.
  -spec create_users(escalus:config(), [escalus_users:resource_spec()]) -> escalus:config().
  create_users(Config, UserSpecs) ->
      Suffix = fresh_suffix(Config),
      FreshSpecs = freshen_specs(Config, UserSpecs, Suffix),
      FreshConfig = escalus_users:create_users(Config, FreshSpecs),
      %% The line below is not needed if we don't want to support cleaning
  