global conf
with open('system_data.txt') as json_file:
    for y in json.load(json_file):
        conf = str(y['boot_config'])

def start():
    global login, conf
    with open(f'user.txt') as json_output:
        data = json.load(json_output)
        global t, login_en, passwd_en
        for t in data:
            login_en = t['login']
            passwd_en = t['password']
    global root, anim_speed
    with open(f'config_{conf}.txt') as json_file:
        data = json.load(json_file)
        for p in data:
            root = bool(p['root'])
            anim_speed = float(p['anim_speed'])
    if (login_en, passwd_en) == ('new', 'new'):
        login = input ('Enter new login: ')
        passwd = input ('Enter new password: ')
        user_data = {}
        user_data['user_data'] = []
        user_data['user_data'].append({
            'login': login,
            'password': passwd
        })
        with open('user.txt', 'w') as out_json:
            json.dump(user_data['user_data'], out_json)
        os.system('cls')
        print ('New account created!')
        time.sleep(1)
        welcome()
    else:
        login = input('Enter login: ')
        if login == '_':
            conf = input ('config_')
            try:
                with open(f'config_{conf}.txt') as json_file:
                    data = json.load(json_file)
                    for p in data:
                        root = bool(p['root'])
                        anim_speed = float(p['anim_speed'])
                        start()
            except:
                print ('ConfigNotFoundError! Choose another config!')
                start()
        password = input ('Enter password: ')
        if (login, password) == (login_en, passwd_en):
            welcome()
        else:
            print ('----------------------------------------\n'
                   '| You entered wrong login or password! |\n'
                   '----------------------------------------')
            start()

.......

def main():
    os.system('cls')
    global root
    global password
    global login
    global version
    global conf
    version = 'AMT OS v.3.2 alpha 2.3.2 build 23'
    print(
        f'-------------------------------------\n| {version} |\n--------------------------------------------------------'
        f'----\n| Enter "commands" to see command list                     |\n| Enter "info" to get information about '
        f'system             |\n------------------------------------------------------------')
    inp_sym = f'{login}|> ' if root == False else f'root|{login}|> '
    command = input (inp_sym).split()

'''
и при этом выскакивает ошибка, что в inp_sym переменная root не найдена
'''