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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_css_class(self, ttype):
 """Return the css class of this token type prefixed with the classprefix option."""

        ttypeclass = _get_ttype_class(ttype)
        if ttypeclass:
            return self.classprefix + ttypeclass
        return ''