I am writing a Python program that takes integer numbers from the user and adds them to a list of numbers, if the number isn't already in the list. This normally isn't difficult but I cannot use the in/not in operator, `index()`, or `insert()` functions to accomplish the task.

After I have created the list, I ask the user if they want to replace any values in the list. If they do, then get the value to find and the replacement value. 

Once again I can't use the in/not in operator or `index()` function to accomplish the task.

My code:

```
def figure_it_out(numbers_list):
    while True:
        number = int(input("Enter the number for the list: "))
        duplicate = False
        for val in numbers_list:
            if number == val:
                duplicate = True
                break

        if duplicate:
            print("Duplicate found")
        else:
            numbers_list.append(number)
            print("Added {}".format(number))

        answer = input("Would you like to add another number? (y/n): ")
        if answer == 'y':
            continue
        else:
            break

    return numbers_list

def replace_number(current_list):
    while True:
        answer = input("Would you like to replace a number? (y/n): ")

        if answer == 'y':
            count = 0
            num_replace = int(input("What number will you replace: "))
            duplicate = False
            for val in current_list:
                count += 1
                if num_replace == val:
                    duplicate = True
                    break

            if duplicate:
                replacment = int(input("Replace with: "))
                current_list[count - 1] = replacment
                print(current_list)
            else:
                print("There is no number in the list.")    
        else:
            break

    return current_list

def main():
    adding_list = []

    cur_list = figure_it_out(adding_list)

    print(cur_list)

    final_list = replace_number(cur_list)

    print("Your final list is: " + str(final_list))

main()

```

Output:

```
Enter the number for the list: 2
Added 2
Would you like to add another number? (y/n): y
Enter the number for the list: 3
Added 3
Would you like to add another number? (y/n): y
Enter the number for the list: 4
Added 4
Would you like to add another number? (y/n): y
Enter the number for the list: 5
Added 5
Would you like to add another number? (y/n): y
Enter the number for the list: 6
Added 6
Would you like to add another number? (y/n): n
[2, 3, 4, 5, 6]
Would you like to replace a number? (y/n): y
What number will you replace: 5
Replace with: 9
[2, 3, 4, 9, 6]
Would you like to replace a number? (y/n): y
What number will you replace: 6
Replace with: 8
[2, 3, 4, 9, 8]
Would you like to replace a number? (y/n): n
Your final list is: [2, 3, 4, 9, 8]

```

Thank you for all the help!