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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 grayspec(k):
 """ List of gray-scale colors in HSV space as web hex triplets. For integer argument k, returns list of `k` gray-scale colors, increasingly light, linearly in the HSV color space, as web hex triplets. Technical dependency of :func:`tabular.spreadsheet.aggregate_in`. **Parameters** **k** : positive integer Number of gray-scale colors to return. **Returns** **glist** : list of strings List of `k` gray-scale colors. """

    ll = .5
    ul = .8
    delta = (ul - ll) / k
    return [GrayScale(t) for t in np.arange(ll, ul, delta)]