signup.py

import os


def SignUp():
    username = input('please enter username: ')
    filename = username + '.txt'
    if os.path.exists(filename):
        print('Username already exists, please choose another one: ')
        SignUp()
    else:
        password = input('please enter password: ')
        file = open(filename, 'w')
        file.write(password)
        file.close()


def SignIn():
    username = input('username: ')
    password = input('password: ')
    filename = username + '.txt'
    try:
        file = open(filename, 'r')
        savepassword = file.read().rstrip()
        file.close()
        if savepassword == password:
            print('Signing in....')
            print('Success')
        else:
            print('Wrong password...')

    except FileNotFoundError:
        print('No such username exists!')


# Program Start Here
SignUp()