Draw rectangle with rounded corners?

[AlexMercier]

How to create a rectangle with rounded corners and border lines using drawsvg?
like this

[a-hefner]

You can specify the radius of the rounded corners with the rx and ry keyword arguments.
Like line width or colour there is no positional argument for this.

import drawsvg as draw

d = draw.Drawing(350, 250)

p = draw.Rectangle(50, 50, 200, 100, rx=20, ry=10,
    stroke_width=2, stroke='lime', fill='black', fill_opacity=0.2)
d.append(p)
d.set_pixel_scale(2)
d.save_svg('example.svg')