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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 laplacian_pyramid_image(shape, n_levels=4, sd=None):
 """Simple laplacian pyramid paramaterization of an image. For more flexibility, use a sum of lowres_tensor()s. Args: shape: shape of resulting image, [batch, width, height, channels]. n_levels: number of levels of laplacian pyarmid. sd: standard deviation of param initialization. Returns: tensor with shape from first argument. """

    batch_dims = shape[:-3]
    w, h, ch = shape[-3:]
    pyramid = 0
    for n in range(n_levels):
        k = 2 ** n
        pyramid += lowres_tensor(shape, batch_dims + (w // k, h // k, ch), sd=sd)
    return pyramid