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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 colorbar(height, length, colormap):
 """Return the channels of a colorbar. """

    cbar = np.tile(np.arange(length) * 1.0 / (length - 1), (height, 1))
    cbar = (cbar * (colormap.values.max() - colormap.values.min())
            + colormap.values.min())

    return colormap.colorize(cbar)