In the "R" language, Hadley Wickham is a superstar. (personal, git)
One of his packages is "lubridate". It has a stack of very useful time/date handling utilities. They are most useful for "speaking human" or in average-person-facing user interfaces.
You should look at the utility here. Things like elapsed time in days, or holiday handling built-in. That might be useful to have in a clean and native package.
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