Write a stored function named fHW$\_9\_$xxxx$($student$\_$id$,$ year$)$ that calculates and returns the total tuition fees a student has incurred for a specific year based on their enrolled courses. The function should meet the following requirements

Case $1$

If the student$\_$id is negative or NULL, return an error message Please enter a valid student$\_$id$.>$ select fHW$\_9\_$xxxx$($null$,2020)$ as output;$>$ select fHW$\_9\_$xxxx$(-1,2020)$ as output;

case$2$

If the year is negative or NULL, return an error message Please enter a valid year.$>$ select fHW$\_9\_$xxxx$(1007,$ null$)$ as output;$>$ select fHW$\_9\_$xxxx$(1007,-1)$ as output;

Case$3$

If both the student$\_$id and year are $0,$ return the message with the total payment for all students across all years and semesters.$>$ select fHW$\_9\_$xxxx$(0,0)$ as output;

Case$4$

If the student$\_$id is not in the system, regardless of whether the year is $0$ or a specific year, return the message: 'Student$\_$id zzzz is not in the system.$\text{'}>$ select fHW$\_9\_$xxxx$(2010,2017)$ as output;

case$5$

If student$\_$id is in the system and the year is $0,$ return the message with total payment for the given student$\_$id across all years.$>$ select fHW$\_9\_$xxxx$(1007,0)$ as output;

Case$6$

If student$\_$id is in the system and the year is $1,$ return the message with the payment for the given student$\_$id for each year.$>$ select fHW$\_9\_$xxxx$(1007,1)$ as output;

Case$7$

If the student$\_$id is $0$ or in the system and year is NOT in the system, return the message: $\text{'}$No student founds for year yyyy is in the system'.$>$ select fHW$\_9\_$xxxx$(0,2200)$ as output;

Case$8$

If the student$\_$id is $0$ and year is the system, return the total payment for the given year across all students.$>$ select fHW$\_9\_$xxxx$(0,2017)$ as output;

Case$9$

If the student$\_$id is $1$ and year is is in the system, return the message with the total payment for the given year for each student.$>$ select fHW$\_9\_$xxxx$(1,2017)$ as output;

Case$10$

If the student$\_$id and$$ year are is in the system, but student$\_$id not enrolled in the give year,$$ return the message Student ID: zzzz not enrolled in year yyyy$.>$ select fHW$\_9\_$xxxx$(1007,2017)$ as output;

Case$11$

If the student$\_$id and year are is in the system and student$\_$id enrolled in the give year, return the message with the total payment for the given student$\_$id and year.$>$ select fHW$\_9\_$xxxx$(1004,2014)$ as output;