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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 with_more_selectors(self, selectors):
 """Return a new ancestry that also matches the given selectors. No nesting is done. """

        if self.headers and self.headers[-1].is_selector:
            new_selectors = extend_unique(
                self.headers[-1].selectors,
                selectors)
            new_headers = self.headers[:-1] + (
                BlockSelectorHeader(new_selectors),)
            return RuleAncestry(new_headers)
        else:
            new_headers = self.headers + (BlockSelectorHeader(selectors),)
            return RuleAncestry(new_headers)