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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 unregister(self, token_to_remove):
 """ Unregister a filter function. :param token_to_remove: The token as returned by :meth:`register`. Unregister a function from the filter chain using the token returned by :meth:`register`. """

        for i, (_, token, _) in enumerate(self._filter_order):
            if token == token_to_remove:
                break
        else:
            raise ValueError("unregistered token: {!r}".format(
                token_to_remove))
        del self._filter_order[i]