I use a code for get all active sessions in a telegram account:
some of my code:

if step == 'delete_sessions_insert_number':
            try:
                phone_appid = apiid_accounts
                phone_apphash = apihash_accounts
                phone_proxy = cursor.execute(f"SELECT `proxy` FROM `sessions` WHERE `phonenumber` = '{text}'").fetchone()[0]
                IP, port,username,password = phone_proxy.split(":")
                sessions_logined = []
                sessions_confirmed = []
                for s in os.listdir('/root/bot/sessions/logined_sessions'):
                    sessions_logined.append(s.replace('.session', ''))
                for s in os.listdir('/root/bot/sessions/confirmed_sessions'):
                    sessions_confirmed.append(s.replace('.session', ''))
                if text in sessions_confirmed:
                    account = tc2(f"sessions/confirmed_sessions/{text}.session", api_id=int(phone_appid) , api_hash=str(phone_apphash), proxy=("socks5", IP, int(port), True, username, password))
                elif text in sessions_logined:
                    account = tc2(f"sessions/logined_sessions/{text}.session", api_id=int(phone_appid) , api_hash=str(phone_apphash), proxy=("socks5", IP, int(port), True, username, password))
                else:
                    await event.reply('phone number not found!', buttons=admin_cancel_markup)
                    return
                await account.connect()
                result_all_sessions = account(functions.account.GetAuthorizationsRequest())
                await account.disconnect()
                await event.reply(f'Sessions: n {str(result_all_sessions)}')

all things is correct but I see an Error:

'coroutine' object has no attribute 'stringify'

in telethon docs are a example for GetAuthorizationsRequest() that use .stringify but result have not this attribute.