This is an adapted version of https://stackoverflow.com/a/8197703
ggplot_colors(n = 6, h = c(0, 360) + 15, l = c(65, 65))
The number of colors in the color palette. If `n` is a vector, get a color palette, that has `length(n)` different base colors. For each item in n, the actual colors are equally spaced on in the luminance range `l` between the upper and lower value.
The hue range.
A vector of length 2 that describes the luminance range
A vector of `sum(n)` colors strings