Resize display resolution using python with cross platform support

Resize display resolution using a python function. It should be cross platform, ie support for windows, linux and mac (it is okay to have multiple cases depending on the operating system)

I have code which I think works on linux (Ubuntu) I am looking for a solution for windows and mac (should support both 32 and 64 bit machines)

def SetResolution(width, height):
    os.popen("xrandr -s "+str(width)+'x'+str(height))

I would also appreciate it if somebody could tell me how I could get the possible display resolutions for windows and mac

my function on linux is this:

def GetResolutions():
    screen = os.popen("xrandr").readlines()
    possibleResolutions = []
    for a in screen:
        data = a.split()
        if len(data)<4:
            width, height = data[0].split('x')
            fps = re.sub("[^0-9.]", "", data[1])
            possibleResolutions.append({'width':int(width),'height':int(height),'fps':float(fps)})
            if '*' in data[1]:
                currentResolution = {'width':int(width),'height':int(height),'fps':float(fps)}
    return possibleResolutions, currentResolution