anchor.diff:      CBal1 = get_balance(CPubkey),
   
       %% Call the contract bid function by Bert.
  -    {_,BidReturn} = call_compute_func(NodeName, BPubkey, BPrivkey,
  -                                      EncodedContractPubkey,
  -                                      <<"bid">>, <<"()">>,
  -                                      #{amount => 100000,fee => Fee}),
  +    {_,#{return := BidReturn}} =
  +        call_compute_func(NodeName, BPubkey, BPrivkey,
  +                          EncodedContractPubkey,
  +                          <<"bid">>, <<"()">>,
  +                          #{amount => 100000,fee => Fee}),
       #{<<"gas_used">> := GasUsed,<<"height">> := Height1} = BidReturn,
   
       %% Set the cost from the amount, decrease and diff in height.
  
positive.code:     {ok, 200, #{<<"block_hash">> := BlockHash}} = get_tx(ContractCallTxHash),
      {ok, 200, BlockHeader} = get_micro_block_header(BlockHash),
  
      {Value, BlockHeader}.
  
  %% error_call_compute_func(NodeName, Pubkey, Privkey, EncodedContractPubkey,
  %%                         Function, Arguments)
  
negative.code: 
      %% Block timestamp.
      ct:pal("Calling timestamp\n"),
      {TimeStampValue, #{header := TSHeader}} =
          call_compute_func(NodeName, CPubkey, CPrivkey,
                            EncodedContractPubkey,
                            <<"timestamp">>, <<"()">>),
      #{<<"value">> := TimeStamp} = decode_data(<<"int">>, TimeStampValue),
      ct:pal("Timestamp ~p\n", [TimeStamp]),
      ?assertEqual(maps:get(<<"time">>, TSHeader), TimeStamp),
  
      %% Block height.
      ct:pal("Calling block_height\n"),
      {HeightValue,#{header := HeightHeader}} =
          call_compute_func(NodeName, DPubkey, DPrivkey,
                            EncodedContractPubkey,
                            <<"block_height">>, <<"()">>),
      #{<<"value">> := BlockHeight} = decode_data(<<"int">>, HeightValue),
      ct:pal("Block height ~p\n", [BlockHeight]),
      ?assertEqual(maps:get(<<"height">>, HeightHeader), BlockHeight),
  
      %% Difficulty.
      ct:pal("Calling difficulty\n"),
      {DiffValue,#{header := DiffHeader}} =
          call_compute_func(NodeName, DPubkey, DPrivkey,
                            EncodedContractPubkey,
                            <<"difficulty">>, <<"()">>),
      #{<<"value">> := Difficulty} = decode_data(<<"int">>, DiffValue),
      ct:pal("Difficulty ~p\n", [Difficulty]),
      #{<<"prev_key_hash">> := DiffKeyHash} = DiffHeader,
  