a collection of geometric shapes, which defined the edge and label of sets in a Venn plot.
use plot_shapes()
to see some of them.
a list with several slots see "?VennPlotData".
The venn
datasets authored by Adrian Dusa (https://CRAN.R-project.org/package=venn).
Parameters used to generate fancy four set ellipses are adopted from VennDiagram
(https://CRAN.R-project.org/package=VennDiagram).