anchor.diff:  
   -spec close_fifo(string(), port()) -> ok.
   close_fifo(FifoName, FifoPort) ->
  -    port_close(FifoPort),
  +    _ = (catch port_close(FifoPort)),
       _ = file:delete(FifoName),
       ok.
   
  
positive.code: 
  -spec send_command(python_interpreter(), string(), [term()]) -> term().
  send_command(#python_interpreter{python_port = PythonPort} = PythonInterpreter, CmdTemplate, Args) ->
      port_command(PythonPort, io_lib:format("try:\n"
          "    mzbench._instruction_end(~s)\n"
          "except:\n"
          "    traceback.print_exc()\n"
          "    mzbench._instruction_failed(sys.exc_info())\n"
          "\n", 
          [io_lib:format(CmdTemplate, Args)])),
      read_python_output(PythonInterpreter).
  
  -spec read_python_output(python_interpreter()) -> term().
  
negative.code:         {PythonPort, {data, {noeol, Line}}} ->
              wait_python_stop(PythonPort, Acc ++ Line)
      after 5000 ->
          _ = (catch port_close(PythonPort)),
          ok
      end.
  
  