anchor.diff:  -export([
   	put_groups/4,
   	put_groups/5,
  +	put_groups/6,
   	remove_groups/4,
  +	remove_groups/5,
  +	remove_groups/6,
   	update_groups/4,
   	update_groups/5,
   	find/3,
  
positive.code: -export([
  	new_dt/1,
  	update_dt/3,
  	group_rawdt/2,
  	find_group_rawdt/2,
  	fold_groups_dt/3,
  
negative.code: 
  -spec put_groups(pid(), bucket_and_type(), binary(), [{binary(), riakacl_group:group()}], [proplists:property()]) -> riakacl_entry:entry().
  put_groups(Pid, Bucket, Key, Groups, Opts) ->
  	update_groups(Pid, Bucket, Key, fun(Gs) -> put_groups_(Groups, Gs) end, Opts).
  
  %% Be careful using this function, in most of the cases you will prefer to pass
  %% to it an entity that has been retrieved using strict quorum (pr = quorum).
  -spec put_groups(pid(), bucket_and_type(), binary(), [{binary(), riakacl_group:group()}], riakacl_entry:entry(), [proplists:property()]) -> riakacl_entry:entry().
  put_groups(Pid, Bucket, Key, Groups, E0, Opts) ->
  	Now = riakacl:unix_time_us(),
  	E1 = update_groups_dt(fun(Gs) -> put_groups_(Groups, Gs) end, Now, E0),
  	put(Pid, Bucket, Key, E1, Opts).
  
  -spec remove_groups(pid(), bucket_and_type(), binary(), [binary()]) -> entry().
  remove_groups(Pid, Bucket, Key, Names) ->
  	update_groups(Pid, Bucket, Key, fun(Gs) -> remove_groups_(Names, Gs) end).
  
  -spec remove_groups(pid(), bucket_and_type(), binary(), [binary()], [proplists:property()]) -> entry().
  remove_groups(Pid, Bucket, Key, Names, Opts) ->
  	update_groups(Pid, Bucket, Key, fun(Gs) -> remove_groups_(Names, Gs) end, Opts).
  
  %% Be careful using this function, in most of the cases you will prefer to pass
  %% to it an entity that has been retrieved using strict quorum (pr = quorum).
  -spec remove_groups(pid(), bucket_and_type(), binary(), [binary()], riakacl_entry:entry(), [proplists:property()]) -> entry().
  remove_groups(Pid, Bucket, Key, Names, E0, Opts) ->
  	Now = riakacl:unix_time_us(),
  	E1 = update_groups_dt(fun(Gs) -> remove_groups_(Names, Gs) end, Now, E0),
  	put(Pid, Bucket, Key, E1, Opts).
  
  -spec update_groups(pid(), bucket_and_type(), binary(), fun((riakacl_group:group()) -> riakacl_group:group())) -> entry().
  update_groups(Pid, Bucket, Key, Handle) ->
  