You are a senior python engineer, you provide python code to answer questions.
To improve your Telegram bot and make it as advanced and user-friendly as possible, you can consider implementing the following enhancements:

1. **Environment Variables for Security**:
   - Ensure that sensitive information like your Telegram API token is not hardcoded. Instead, load it from environment variables securely.

2. **Comprehensive Error Handling**:
   - Improve error messages to make them more informative. You could inform users of possible reasons for the failure and suggest steps for resolution.

3. **User Engagement**:
   - Add more interactive commands to improve engagement, such as `/help` to show available commands and usage examples.
   - Consider adding features like `/feedback` or `/settings` to enhance user interaction.

4. **Persistent User Sessions**:
   - Store user history in a database to maintain sessions across restarts or crashes. This approach provides a consistent user experience.

5. **Customization Options**:
   - Allow users to set preferences (language, tone, etc.) and save these settings for personalized interactions.

6. **Natural Language Processing Enhancements**:
   - Integrate more advanced NLP models to provide better, context-aware answers.
   - Train the model to understand different languages if you’re targeting a global audience.

7. **Use of Webhooks**:
   - Switch from polling to webhooks for better performance and efficiency, as webhooks consume fewer resources.

8. **Advanced Logging and Monitoring**:
   - Implement more sophisticated logging, including user interactions and errors, to monitor bot usage and diagnose issues quickly.

9. **Rich Media Support**:
   - Enable the bot to send and receive different types of content such as images, audio, documents, and more to make the conversation more dynamic.

10. **Testing and Quality Assurance**:
   - Set up a testing framework to ensure the bot's functionality is tested thoroughly before deployment. Automated tests can catch errors early and gauge the chatbot’s response quality.

Here’s a sample of how you might start implementing some of these suggestions:

### Enhanced Code Example

```python
import logging
from telebot import TeleBot, types
from telebot.types import Message
from dotenv import load_dotenv
from gemma_model import ModelClient
import os

# Load environment variables from a .env file
load_dotenv()

model_client = ModelClient()
telegram_api_token = os.getenv('TELEGRAM_API_TOKEN')

# Setup logging
logging.basicConfig(
    format='%(asctime)s - %(name)s - %(levelname)s - %(message)s',
    level=logging.INFO
)

# Instantiate the bot
bot = TeleBot(telegram_api_token)

# Dictionary to keep track of user histories
user_histories = {}


@bot.message_handler(commands=['start', 'help'])
def send_welcome(message: Message):
    welcome_text = (
        "Hello! I am your advanced chatbot.\n"
        "Here are some commands to get you started:\n"
        "/start - Restart the bot\n"
        "/clear - Clear the conversation history\n"
        "/settings - Customize your experience\n"
        "/feedback - Provide feedback about the bot\n"
        "Start talking to me by sending a message!"
    )
    bot.reply_to(message, welcome_text)


@bot.message_handler(commands=['clear'])
def clear_history(message: Message):
    user_id = message.from_user.id
    user_histories.pop(user_id, None)
    bot.reply_to(message, 'Your history has been cleared!')


@bot.message_handler(commands=['feedback'])
def feedback(message: Message):
    bot.send_message(message.chat.id, "Please share your feedback with us!")


@bot.message_handler(commands=['settings'])
def settings(message: Message):
    markup = types.ReplyKeyboardMarkup(row_width=2)
    markup.add('Change Language', 'Set Notification Preferences')
    bot.send_message(message.chat.id, "Settings options:", reply_markup=markup)


@bot.message_handler(func=lambda message: True)
def chat(message: Message):
    try:
        user_id = message.from_user.id
        user_message = message.text
        history = user_histories.setdefault(user_id, [])
        sys_prompt = "Your system prompt here"

        response = model_client.get_response(user_message, history, sys_prompt)

        history.append((user_message, response))
        bot.reply_to(message, response)
    except Exception as e:
        bot.reply_to(message, "An error occurred. Please try again.")
        logging.error(f"Error in chat handler: {e}")


if __name__ == '__main__':
    try:
        bot.polling(none_stop=True)
    except Exception as e:
        logging.error(f"Error occurred: {e}")
```

This refactored code provides the foundation for enhanced functionality and usability, with the potential to further expand according to your specific requirements and user feedback.