Draw the German flag in the center of the canvas. It is 165 units wide and 100 units high.

The flag has three equal horizontal stripes. From top to bottom, color them black, red, and yellow. Draw a black outline around each stripe.

Use a function named draw_rectangle(x0, y0, width, height, color) to draw each stripe. The x0 and y0 values mark the top-left corner of each rectangle.