How to customize the inflection point circle, or how to get the coordinates of the point.

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How to customize inflection point circle

circleColors

```
set.circleColors = [UIColor.white]
```
I want to customize this circle,I want to customize this circle,

The issue mentions the circleColors setting and includes an image, but names no source file, entry point, or test. First clarify whether the request is for circle styling, point coordinates, or documentation, then identify the relevant chart component and define the expected customization behavior before estimating a change.

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