### Expected Behavior


### Actual Behavior

<!-- In case of a bug, attach full exception traceback. Please
     wrap verbatim code/output in Markdown fenced code blocks:
     https://bit.ly/3nEvlHP -->


### Steps to Reproduce

<!-- In case of a bug, attach steps and code sample
     with which the bug can be reproduced. -->

1.
2.
3.

```python

python code goes here

```

### Additional info

<!-- screenshots, code snippets, ... -->

- Backtesting version: 0.?.?   <!-- From backtesting.__version__ -->
- `bokeh.__version__`:
- OS:
