In question $4,$ you will build a class CourseRegistry that store all the courses in a school. The class will use hash table $($backed by Python list$)$ with separate chaining. Python built$-$in function hash$()$ is used to calculate hash code of a course using the course code as key. The calculated hash code will then map to corresponding index position of the hash table using a modulo operator. The constructor is provided in the Assignment Template.

$($a$)$ Method insert$()$ is used to add a course into course registry. Complete the method with the specifications below:

$1)$ Take one input course $($type Course$).$ Validate its type. Raise an error and stop the program if the input type is invalid.

$2)$ Create a LLNode object with course.code as key and course as value $($the class LLNode is provided in the Assignment Template; do not change the code of the LLNode class and do not use other implementations of linked lists$).$

$3)$ Determine the hash table index by calling hash$($course$.$code$)\%$ self.capacity and insert the LLNode object to the front of the linked list.

$4)$ Increment the size attribute by $1.$

$($b$)$ Method search$()$ is used to find and return a course from the course registry. Complete the

method with the specifications below:

$1)$ Take one input code $($type str$).$ Validate its type. Raise an error and stop the program if the input type is invalid.

$2)$ Determine the hash table index by calling hash$($code$)\%$ self.capacity.

$3)$ Search along the linked list to see if any matching LLNode with key equals to the inputted code. If found, return the value attribute of the LLNode. Otherwise, return

None.

$($c$)$ Run the testing code provided in the Assignment Template. It should produce the following

outputs $($excluding the line numbers$).$ Do not alter the testing code.

$1.$ None

$2.$ Data Structures

$3.$

$4.$ Register Chan TM $22061762$A successful.

$5.$ Register CHOW MP $22167034$A successful.

$6.$ Register LAM CS $22118617$A successful.

$7.$ Register LEUNG WA $22018089$A successful.

$8.$ Register LI CC $22134887$A successful.

$9.$ Course full. Put LIU MK $22052452$A in waiting queue.

$10.$ Course full. Put NG KY $22018110$A in waiting queue.

$11.$ Course full. Put SHEK CL $22161668$A in waiting queue.

$12.$ Course full. Put TSE David $22158990$A in waiting queue.

$13.$ Course full. Put WONG KM $22153656$A in waiting queue.

$14.$

$15.$ Remove CHOW MP $22167034$A successful.

$16.$ Register LIU MK $22052452$A successful.

$17.$

$18.$ Course code: SEHH$2239$

$19.$ Course title: Data Structures

$20.$ Course size: $5/5$

$21.$ Registered students:

$22.22018089$A Name: LEUNG WA$,$ ID: $22018089$A

$23.22052452$A Name: LIU MK$,$ ID: $22052452$A

$24.22061762$A Name: Chan TM$,$ ID: $22061762$A

$25.22118617$A Name: LAM CS$,$ ID: $22118617$A

$26.22134887$A Name: LI CC$,$ ID: $22134887$A

$27.$ Students in queue:

$28.$ Queue size: $4/8$

$29.$ Name: NG KY$,$ ID: $22018110$A

$30.$ Name: SHEK CL$,$ ID: $22161668$A

$31.$ Name: TSE David, ID: $22158990$A

$32.$ Name: WONG KM$,$ ID: $22153656$A

###### Question $4$ ###### $($do not change this line$)$

class CourseRegistry$($object$)$: # $($do not change this line$)$

def $\_\_$init$\_\_($self$,$ capacity$=10)$: # $($do not change this function$)$

self.capacity $=$ capacity

self.hashtable $=[$None$]*$ capacity

self.size $=0$

def insert$($self$,$ course$)$: # $($do not change this line$)$

#################################################################

# Question $4($a$)$

#################################################################

# Start of your code

# End of your code

#################################################################

pass # $($do not change this line$)$

def search$($self$,$ code$)$: # $($do not change this line$)$

#################################################################

# Question $4($b$)$

#################################################################

# Start of your code

# End of your code

#################################################################

pass # $($do not change this line$)$

registry $=$ CourseRegistry$()$

# Insert $1000$ dummy courses to the registry to populate the hash table

for code in range$(1000)$:

course $=$ Course$($f$"$HKCC$\{$code:$04$d$\}",$ "DUMMY", $30)$

registry.insert$($course$)$

course$1=$ Course$("$SEHH$2239",$ "Data Structures", $5)$

course$2=$ Course$("$BHMH$2103",$ "Advertising and Promotion", $10)$

registry.insert$($course$1)$

registry.insert$($course$2)$

print$($registry$.$search$("$SEHH$2042"))$

sehh$2239=$ registry.search$("$SEHH$2239")$

print$($sehh$2239.$title$)$

print$()$

slist $=[$Student$(\text{'}$Chan TM$\text{'},\text{'}22061762$A$\text{'}),$ Student$(\text{'}$CHOW MP$\text{'},\text{'}22167034$A$\text{'}),$ Student$(\text{'}$LAM CS$\text{'},\text{'}22118617$A$\text{'}),$

Student$(\text{'}$LEUNG WA$\text{'},\text{'}22018089$A$\text{'}),$ Student$(\text{'}$LI CC$\text{'},\text{'}22134887$A$\text{'}),$ Student$(\text{'}$LIU MK$\text{'},\text{'}22052452$A$\text{'}),$

Student$(\text{'}$NG KY$\text{'},\text{'}22018110$A$\text{'}),$ Student$(\text{'}$SHEK CL$\text{'},\text{'}22161668$A$\text{'}),$ Student$(\text{'}$TSE David',$\text{'}22158990$A$\text{'}),$

Student$(\text{'}$WONG KM$\text{'},\text{'}22153656$A$\text{'})]$

for e in slist:

sehh$2239.$addStudent$($e$)$

print$()$

sehh$2239.$removeStudent$($slist$[1])$

print$()$

sehh$2239.$PrintCourse$()$