Create a class `MonthlyPeriod` that provides a method to calculate the period between two given dates in terms of months and years. The dates will be provided in the format `yyyy-MM-dd`.
In case of any error the method `calculatePeriod` should return `Error`
> 💡 Going to the past is possible!
### Expected Class
```java
import java.time.LocalDate;
import java.time.Period;
import java.time.format.DateTimeFormatter;
public class MonthlyPeriod {
public String calculatePeriod(String startDate, String endDate) {
// Implementation to calculate the period between two dates in months and years