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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 _get_back_up_generator(frame_function, *args, **kwargs):
 """Create a generator for the provided animation function that backs up the cursor after a frame. Assumes that the animation function provides a generator that yields strings of constant width and height. Args: frame_function: A function that returns a FrameGenerator. args: Arguments for frame_function. kwargs: Keyword arguments for frame_function. Returns: a generator that generates backspace/backline characters for the animation func generator. """

    lines = next(frame_function(*args, **kwargs)).split('\n')
    width = len(lines[0])
    height = len(lines)
    if height == 1:
        return util.BACKSPACE_GEN(width)
    return util.BACKLINE_GEN(height)