Linked List

# Linked Lists Exercise - My Answer
import time
import os


class Node:
    def __init__(self, contents=None, next=None):
        self.contents = contents
        self.next = next

    def get_contents(self):
        return self.contents

    def __str__(self):
        return str(self.contents)


def print_list(node):
    while node:
        print(node.get_contents())
        node = node.next
    print()


def add_to_list():
    print("Current linked list:")
    print_list(node1)
    try:
        print("If you wish to select a different option enter BACK")
        node_location = input("Enter the location you desire you data to be: ")
        if node_location == "BACK":
            print("Returning to menu...")
            time.sleep(1)
            os.system('cls')
            return main()
        node_location = int(node_location)
    except:
        print("This should be a number!")
        return add_to_list()
    temp = "node" + str(node_location)
    temp1 = "node" + str(node_location - 1)
    added_node = Node(input("Enter the desired data: "))
    try:
        globals()[temp1].next = added_node
        added_node.next = globals()[temp]
    except:
        pass
    print("The linked list now:")
    if (node_location - 1) == 0:
        added_node.next = node1
        print_list(added_node)
    else:
        print_list(node1)
    os.system('cls')
    return main()


def delete_node():
    print("Current linked list:")
    print_list(node1)
    try:
        print("If you wish to select a different option enter BACK")
        location = input("Enter the location you want to delete: ")
        if location == "BACK":
            print("Returning to menu...")
            time.sleep(1)
            os.system('cls')
            return main()
        location = int(location)
    except:
        print("This should be a number!")
        return delete_node()
    temp = "node" + str(location)
    if globals()[temp] is None:
        print("This node does not exist")
        return delete_node()
    temp1 = "node" + str(location - 1)
    temp2 = "node" + str(location + 1)
    print("deleting:", globals()[temp].contents, "\n")
    globals()[temp1].next = globals()[temp2]
    os.system('cls')
    return main()


def main():
    print("Current linked list:")
    print_list(node1)
    decision = input("Do you wish to add or delete: ")
    os.system('cls')
    if decision == "add":
        add_to_list()
    elif decision == "delete":
        delete_node()
    else:
        print("Invalid input")
        return main()


node0 = None
node1 = Node("Bob")
node2 = Node("Car")
node3 = Node("Sky")
node4 = Node("Skidipap")
node1.next = node2
node2.next = node3
node3.next = node4
main()