TheTimgor

def fast_rot(width, height, raster):
    for j in range(0, width):
        for k in range(0, height):
            to = width * height - (height * j + k + 1)
            i = (width - j - 1) + width * k
            if i != to:
                while i > to:
                    i = width * (height - (i % height) - 1) + ((i - (i % height)) / height)
                buffer = raster[int(i)]
                raster[int(i)] = raster[int(to)]

TheTimgor

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#       @moeshitbot, by timgor |  timgor.moe
#       annotated source code
#       
#   this is my shitty cute anime pics twitter bot.