Ahmed is amazing

import sys
from pathlib import Path


def check_for_file():
    while True:
        filename = input("\nFilename: ")
        if filename[-4:] != ".txt":
            filename += ".txt"
        file = Path(filename)
        if file.is_file():
            return filename
        else:
            print(f"'{filename}' does not exist in this directory.")


def find_contact():
    filename = check_for_file()
    file = open(filename, "r")
    contact_name = input("\nContact name: ").lower()
    lines = file.read().splitlines()
    for index, line in enumerate(lines):
        if contact_name in line:
            print(f"{contact_name.title()} found at index {index}.")
    file.close()
    menu()


def create_contact():
    while True:
        print("\nCreate contact\n1) Add to existing contact book\n2) Create new contact book\n")
        try:
            option = int(input("Option: "))
            if option == 1:
                check_for_file()
                break
            elif option == 2:
                # create new file
                break
            else:
                print("Please choose an option between 1 and 2.")
        except ValueError:
            print("Please choose an option between 1 and 2.")
    print("We're out!")
    menu()


def menu():
    while True:
        print("\nMenu\n1) Find contact\n2) Create contact\n3) Quit\n")
        try:
            option = int(input("Option: "))
            if option == 1:
                find_contact()
            elif option == 2:
                create_contact()
            elif option == 3:
                sys.exit()
            else:
                print("Please choose an option between 1 and 3.")
        except ValueError:
            print("Please choose an option between 1 and 3.")


print("Contact Book")
menu()