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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 most_recent_common_ancestor(self, *ts):
 """Find the MRCA of some tax_ids. Returns the MRCA of the specified tax_ids, or raises ``NoAncestor`` if no ancestor of the specified tax_ids could be found. """

        if len(ts) > 200:
            res = self._large_mrca(ts)
        else:
            res = self._small_mrca(ts)

        if res:
            (res,), = res
        else:
            raise NoAncestor()
        return res