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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 cubehelix_palette(n_colors=6, start=0, rot=.4, gamma=1.0, hue=0.8, light=.85, dark=.15, reverse=False, as_cmap=False):
 """Make a sequential palette from the cubehelix system. This produces a colormap with linearly-decreasing (or increasing) brightness. That means that information will be preserved if printed to black and white or viewed by someone who is colorblind. "cubehelix" is also availible as a matplotlib-based palette, but this function gives the user more control over the look of the palette and has a different set of defaults. Parameters n_colors : int Number of colors in the palette. start : float, 0 <= start <= 3 The hue at the start of the helix. rot : float Rotations around the hue wheel over the range of the palette. gamma : float 0 <= gamma Gamma factor to emphasize darker (gamma < 1) or lighter (gamma > 1) colors. hue : float, 0 <= hue <= 1 Saturation of the colors. dark : float 0 <= dark <= 1 Intensity of the darkest color in the palette. light : float 0 <= light <= 1 Intensity of the lightest color in the palette. reverse : bool If True, the palette will go from dark to light. as_cmap : bool If True, return a matplotlib colormap instead of a list of colors. Returns ------- palette : list or colormap References Green, D. A. (2011). "A colour scheme for the display of astronomical intensity images". Bulletin of the Astromical Society of India, Vol. 39, p. 289-295. """

    cdict = mpl._cm.cubehelix(gamma, start, rot, hue)
    cmap = mpl.colors.LinearSegmentedColormap("cubehelix", cdict)

    x = np.linspace(light, dark, n_colors)
    pal = cmap(x)[:, :3].tolist()
    if reverse:
        pal = pal[::-1]

    if as_cmap:
        x_256 = np.linspace(light, dark, 256)
        if reverse:
            x_256 = x_256[::-1]
        pal_256 = cmap(x_256)
        cmap = mpl.colors.ListedColormap(pal_256)
        return cmap
    else:
        return pal