Suggestion: Make docker-compose.yml use environment variables or .env

with changes like 

```
<<<<<<< 
      - OPENAI_API_KEY=<your_openai_key>
=======
      - OPENAI_API_KEY=${OPENAI_API_KEY}
>>>>>>>
```

one can make docker-compose.yml to use environment variables or  keys from `.env ` , and actually using `.env` (and having it in `.gitignore`) would be very elegant way .