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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 _linear_inverse_kamb(cos_dist, sigma=3):
 """Kernel function from Vollmer for linear smoothing."""

    n = float(cos_dist.size)
    radius = _kamb_radius(n, sigma)
    f = 2 / (1 - radius)
    cos_dist = cos_dist[cos_dist >= radius]
    count = (f * (cos_dist - radius))
    return count, _kamb_units(n, radius)