The render flags used to define the window.
The border width of your window in pixels: either 0, or the value of the border_width flag of your window.
A list in the format (l,t,r,b) which is the widths of the left, top, right and bottom borders, in pixels.
This function uses the render information about your window to set border widths for the left, top, right, and bottom sides. The border_width can be set to 0, or to the border_width value of your window.