+1 to the use of context manager here to put an algorithm into a different trading context/environment.

Small note, the with statement has the ability to do the context/object creation and assignment in one line.

e.g.

```
with trading.TradingEnviroment(bm_symbol='^FTSE', exchange_tz='Europe/London') as lse:
```

Could do away with the `lse` variable all together, but it's a nice to have available when debugging.