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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _open_fbdev(fbdev=None):
 """Return the framebuffer file descriptor. Try to use the FRAMEBUFFER environment variable if fbdev is not given. Use '/dev/fb0' by default. """

        dev = fbdev or os.getenv('FRAMEBUFFER', '/dev/fb0')
        fbfid = os.open(dev, os.O_RDWR)
        return fbfid