Add curly brackets for axis area in a plot [closed]

I would like to add curly brackets next to the axis in a plot. The curly brackets should look something like this:

All credits to this answer, I only did some messy adjustments. Adding xpd=NA allows you to draw outside of the plot:

# function to draw curly braces
# x, y position where to put the braces
# range is the length of the brace
# position: 1 vertical, 2 horizontal
# direction: 1 left/down, 2 right/up
# depth controls width of the shape

CurlyBraces <- function(x0, x1, y0, y1, pos = 1, direction = 1, depth = 1) {

    a=c(1,2,3,48,50)    # set flexion point for spline
    b=c(0,.2,.28,.7,.8) # set depth for spline flexion point

    curve = spline(a, b, n = 50, method = "natural")$y * depth

    curve = c(curve,rev(curve))

    if (pos == 1){
        a_sequence = seq(x0,x1,length=100)
        b_sequence = seq(y0,y1,length=100)  
    }
    if (pos == 2){
        b_sequence = seq(x0,x1,length=100)
        a_sequence = seq(y0,y1,length=100)      
    }

    # direction
    if(direction==1)
        a_sequence = a_sequence+curve
    if(direction==2)
        a_sequence = a_sequence-curve

    # pos
    if(pos==1)
        lines(a_sequence,b_sequence, lwd=1.5,   xpd=NA) # vertical
    if(pos==2)
        lines(b_sequence,a_sequence, lwd=1.5, xpd=NA) # horizontal

}

windows(width=5, height=5)
par(oma=c(2,0,0,2))
plot(c(),c(), xlim=c(0,11), ylim=c(0,11), xlab='')
# horizontal brace
CurlyBraces(x0=2,  x1=8,  y0=-3, y1=-3, pos = 2, direction = 2, depth=1.5)
# vertical brace
CurlyBraces(x0=12, x1=12, y0=2, y1=6, pos = 1, direction = 1, depth=0.5)