Set operations for many sets. The base functions for set operations in R are good for only two sets. This package uses 'purrr' to find the union, intersection and difference of three or more sets. Further, based on 'ggplot2' and 'ggforce', Venn diagram can be drawn for two or three sets (Venn diagrams with four or more sets are terrible, please use 'UpSet' if you have lots of sets). Finally, enrichment test can be applied to two sets whether an overlap is statistically significant or not.