(a) Redefine the addition operation of LinkList to create a new LinkList as following: L3=L1 + L2 where L1, L2 and L3 are same class LinkList. e.g. if L1 = 1->2 and L2 = 5->8, then L3 will be 1->2->5->8 Provide 3 more testing cases for this question. Exceptional cases should be considered. (b) Redefine the comparing operation of two LinkList such that if all element inside the list and their order are consistence, it will return True. Otherwise, return False. L1=L2 e.g. if L1 = 1->2 and L2 = 1->2, then it will return true. If L1 =1->2 and L2 = 2->1, then it will return false. Provide 3 more testing cases for this question. Exception cases should be considered. class Linked List: def __init__(self): self.head = None self.tail = None def display (self): current_node = self.head while current_node: print(current_node.data, end=" ") current_node = current_node.next print() def append(self, node): if self.head is None: self.head node self.tail = node else: self.tail.next = node self.tail = node