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

    n = float(cos_dist.size)
    f = 2 * (1.0 + n / sigma**2)
    count = np.exp(f * (cos_dist - 1))
    units = np.sqrt(n * (f/2.0 - 1) / f**2)
    return count, units