3. Please justify why the linked list toolkit functions are not member functions of the node class? // FUNCTIONS for the linked list toolkit std::size_t list_length (const node* head_ptr); void list_head_insert (node* & head_ptr, const node::value_type& entry); void list_insert (node* previous_ptr,const node::value_type& entry); node* list_search (node* head_ptr, const node::value_type& target); const node* list_search (const node* head_ptr, const node::value_type& target); node* list_locate (node* head_ptr, std::size_t position); const node* list_locate (const node* head_ptr, std::size_t position); void list_head_remove (node* & head_ptr); void list_remove (node* previous_ptr); void list_clear (node* & head_ptr); void list_copy (const node* source_ptr, node* & head_ptr, node* & tail_ptr)