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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_names_list(self, format_strings):
 """ Returns a list of color names in ``format_string``. :param format_strings: Accepts a format string or a list of format strings. """

        if not format_strings:
            return []
        if not getattr(self._py3status_module, "thresholds", None):
            return []
        if isinstance(format_strings, basestring):
            format_strings = [format_strings]
        names = set()
        for string in format_strings:
            names.update(self._formatter.get_color_names(string))
        return list(names)