I want to draw the median segments in geom_boxplot() with custom colors. I found a solution for R-ggplot2 with gg_build() which provides x, xend, y, yend inputs for geom_segment() to overlay the median segments on the boxplot.

I couldn’t find gg_build() equivalent functionality in plotnine, so my approach is to construct a new dataframe which calculates these 4 values for each group, needed by geom_segment.

To that end, I know how to get y and yend for each group – these values are the group medians. However, not clear on how to calculate x and xend? Since I need to find a x-value for each group (for my use-case, groups names are str type). Additionally, I also require the box-width used in geom_boxplot().

Any suggestions on how to extract/calculate those?

Thanks!