Linked List Phone Book:

def ll_insert(head, name, phone):
    new_node = {'name': name, 'phone' : phone, 'next': None}
    if head is None:
        return new_node
    if head['name'] == name:
        head['phone'] = phone
        return head
    current = head 
    while current['next'] is not None:
        if current['next']['name'] == name:
            current['next']['phone'] = phone
            return head
        current = current['next']
    current['next'] = new_node
    return head 
def ll_find(head, name):
    current = head
    while current != None:
        if current['name']==name:
            return current['phone']
        current = current['next']
    return None
def ll_delete(head, name):
    if head is None:
        return None
    if head['name'] == name:
        return head['next']
    current = head    
    while current['next'] is not None:
        if current['next']['name'] == name:
            current['next']==current['next']['next']
            return head
        current=current['next']
    return head
def ll_list_all(head): 
    records= []
    current = head 
    while current is not None:
        records.append({'name': current['name'], 'phone': current['phone']})
        current = current['next']
    records.sort(key=lambda x: x['name'])
    return records 
def ll_print_all(head):
    records = ll_list_all(head)
    for record in records:
        print(f"{record['name']}: {record['phone']}")
head = None
#добавление записей 
print("\n1. Добавляем записи в список:")
head = ll_insert(head, "Анна", "123")
head = ll_insert(head, "Сергей", "234")
head = ll_insert(head, "Георгий", "345")
head = ll_insert(head, "Виктория", "456")
ll_print_all(head)
#Обновляем номер
print("\n2. Добавляем новую запись:")
head = ll_insert(head, "Антон", "666")
ll_print_all(head)
    
# Поиск записей
print(f"\n3. Производим поиск записей: \nПоиск Алисы: {ll_find(head, 'Анна')}")
print(f"Поиск Елены: {ll_find(head, 'Елена')}")
    
# Удаление записей
print("\n4. Удаляем Владимира:")
head = ll_delete(head, "Владимир")
ll_print_all(head)
    
print("\n5. Удаляем Антона:")
head = ll_delete(head, "Антон")
ll_print_all(head)
    
print("\n6. Пробуем удалить несуществующую запись:")
head = ll_delete(head, "Некто")
ll_print_all(head)