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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 _format_title_string(self, title_string):
 """ format vlc's title """

        sp = title_string.split(self.icy_tokkens[0])
        if sp[0] == title_string:
            ret_string = title_string
        else:
            ret_string = self.icy_title_prefix + sp[1]
        return self._title_string_format_text_tag(ret_string)