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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 _render_str(self, string):
 """Returned a unicodified version of the string"""

        if isinstance(string, StrLabel):
            string = string._render(string.expr)
        string = str(string)
        if len(string) == 0:
            return ''
        name, supers, subs = split_super_sub(string)
        return render_unicode_sub_super(
            name, subs, supers, sub_first=True, translate_symbols=True,
            unicode_sub_super=self._settings['unicode_sub_super'])