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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 get_color_index(self, colors, refresh=False):
 """Get color index. Refresh data from Vera if refresh is True, otherwise use local cache. """

        if refresh:
            self.refresh_complex_value('SupportedColors')

        sup = self.get_complex_value('SupportedColors')
        if sup is None:
            return None

        sup = sup.split(',')
        if not set(colors).issubset(sup):
            return None

        return [sup.index(c) for c in colors]