anchor.diff:  			remove_session(SessionAttributes, T, [H | T])
   	end;
   remove_session(SessionAttributes, [], Acc) ->
  -erlang:display({?MODULE, ?LINE, SessionAttributes, lists:reverse(Acc)}),
   	lists:reverse(Acc).
   
   -spec add_session(SessionAttributes, SessionList) -> SessionList
  
positive.code: rate4(_Protocol, #subscriber{enabled = false} = Subscriber, _Price,
  		_Validity, initial, _DebitAmounts, _ReserveAmounts,
  		SessionAttributes) ->
  erlang:display({?MODULE, ?LINE, disabled}),
  	rate6(Subscriber, initial, 0, 0, 0, 0, SessionAttributes);
  rate4(radius, Subscriber, Price, Validity,
  		initial, [], [], SessionAttributes) ->
  erlang:display({?MODULE, ?LINE, SessionAttributes}),
  	rate5(Subscriber, Price, Validity, initial,
  			0, get_reserve(Price), SessionAttributes);
  rate4(radius, Subscriber, #price{units = Units} = Price, Validity,
  
negative.code: 		[#bucket{units = Type, termination_date = Expires,
  		remain_amount = Remain, reservations = Reservations} = B | T],
  		Charged, Acc) ->
  	case lists:keytake(SessionId, 3, Reservations) of
  		{value, {_, Amount, _}, NewReservations} when Amount >= Charge,
  				((Expires == undefined) or (Now < Expires)) ->
  