import os
from os import system

system('clear')
with open('file3.txt', 'w') as file:
    file.write("I am learning to use files")
    file.close

while True:
    content = input('What new content to want to add? >> ')
    with open('file3.txt', 'a') as file:
        file.write(f'\n{content}')
        file.close
    response = input('Do you want to add more content? [Y/N] >> ')
    if(str.upper(response) == 'N'):
        break