What is the most elegant way to implement ribbons?

Nobody has claimed this yet.

I am currently thinking about the most elegant way to display 1-2 scatter lines below the chart.
Are there any ideas from others who have already implemented this?

These are my first ideas:

```
import mplfinance as mpf

output = sp_500 ['2021-01-01':].copy()

output["sma_above"] = np.where (output.Close > output.sma, output.sma, np.nan)
output["sma_below"] = np.where (output.Close < output.sma, output.sma, np.nan)

output["ribbon_above"] = np.where (output.Close > output.sma, 1, np.nan)
output["ribbon_below"] = np.where (output.Close < output.sma, 1, np.nan)

add_plt = [
mpf.make_addplot(output["sma_above"],color="green"),
mpf.make_addplot(output["sma_below"],color="red"),
mpf.make_addplot(output["ribbon_above"], panel=1, color="g", type='scatter'),
mpf.make_addplot(output["ribbon_below"], panel=1, color="r", type='scatter'),
]

mpf.plot(
output,
addplot=add_plt,
figsize=(16, 9),
style="charles",
type="candle",
title='S&P 500 - weekly',
datetime_format='%d.%m.%y',xrotation=45,
)
```

Start by reviewing the issue's example calls to mpf.make_addplot and mpf.plot, including the separate panel and scatter settings. The issue does not name files or tests, so the first step is to locate those entry points and determine the intended ribbon API. Done would require an agreed design and a working way to display ribbons below the chart.

Written by the indexing model from the issue text.