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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 mark_rewrite(self, *names):
 """Mark import names as needing to be re-written. The named module or package as well as any nested modules will be re-written on import. """

        already_imported = set(names).intersection(set(sys.modules))
        if already_imported:
            for name in already_imported:
                if name not in self._rewritten_names:
                    self._warn_already_imported(name)
        self._must_rewrite.update(names)