anchor.diff:      ListOfLists = lists:reverse([[K,V]||{K,V} <- PropList]),
       list_to_tuple(lists:foldl(
               fun([K, V], Acc) ->
  -                    [K,V|Acc] 
  +                    [K,V|Acc]
               end, [], ListOfLists)).
   
   list_to_proplist([], Acc) -> Acc;
  
positive.code: -type error_m(X) :: X|{error, any()}.
  
  % Number of seconds between beginning of gregorian calendar and 1970
  -define(GREGORIAN_SECONDS_1970, 62167219200). 
  -compile(export_all).
  -ifdef(TEST).
  -compile(export_all).
  
negative.code: execute({WriteMode, ReadMode, Connection, Database}, Fun) ->
      mongo:do(WriteMode, ReadMode, Connection, Database, Fun) ;
  execute({WriteMode, ReadMode, Connection, Database, User, Password}, Fun) ->
      mongo:do(WriteMode, ReadMode, Connection, Database,
  	     fun() ->
  		     case mongo:auth(User,Password) of
  			 true ->
  