import { default } from "https://deno.land/x/ramda@v0.27.2/source/reduceBy.js";
Groups the elements of the list according to the result of calling
the String-returning function keyFn on each element and reduces the elements
of each group to a single value via the reducer function valueFn.
This function is basically a more general groupBy function.
Acts as a transducer if a transformer is given in list position.