### Install and Run python-telegram-bot

Source: https://python-telegram-bot.org/index

These shell commands show how to install the python-telegram-bot library and run a Python bot script. The first command installs or upgrades the library to the latest stable version using pip. The second command executes your bot script.

```bash
$ pip install python-telegram-bot --upgrade
$ python bot.py
```

--------------------------------

### Create a Telegram Bot with python-telegram-bot

Source: https://python-telegram-bot.org/index

This Python code snippet demonstrates how to build a basic Telegram bot using the python-telegram-bot library. It defines a handler for the '/hello' command which replies with a greeting to the user. Ensure you replace 'YOUR TOKEN HERE' with your actual bot token.

```python
from telegram import Update
from telegram.ext import ApplicationBuilder, CommandHandler, ContextTypes


async def hello(update: Update, context: ContextTypes.DEFAULT_TYPE) -> None:
    await update.message.reply_text(f'Hello {update.effective_user.first_name}')


app = ApplicationBuilder().token("YOUR TOKEN HERE").build()

app.add_handler(CommandHandler("hello", hello))

app.run_polling()
```

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