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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 save(self):
 # type: () -> None """Save the currentin-memory state. """

        self._ensure_have_load_only()

        for fname, parser in self._modified_parsers:
            logger.info("Writing to %s", fname)

            # Ensure directory exists.
            ensure_dir(os.path.dirname(fname))

            with open(fname, "w") as f:
                parser.write(f)