code: func (l *JSONLogger) CaptureEnd(output []byte, gasUsed uint64, t time.Duration, err error) error {
  	type endLog struct {
  		Output  string              `json:"output"`
  		GasUsed math.HexOrDecimal64 `json:"gasUsed"`
  		Time    time.Duration       `json:"time"`
  		Err     string              `json:"error,omitempty"`
  	}
  	if err != nil {
  		return l.encoder.Encode(endLog{common.Bytes2Hex(output), math.HexOrDecimal64(gasUsed), t, err.Error()})
  	}
  	return l.encoder.Encode(endLog{common.Bytes2Hex(output), math.HexOrDecimal64(gasUsed), t, ""})
  }
docs: // CaptureEnd is triggered at end of execution.