import os

from telegram import Update
from telegram.ext import Application, CommandHandler, ContextTypes

async def start(update: Update, context: ContextTypes.DEFAULT_TYPE) -> None:
    await update.message.reply_text("Привет! Команды: /help")

def main() -> None:
    token = os.environ["BOT_TOKEN"]
    app = Application.buildertoken(token).build()
    app.add_handler(CommandHandler("start", start))
    app.run_polling()

if __name__ == "__main__":
    main()