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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 split_flanks(self, _, result):
 """Return `result` without flanking whitespace. """

        if not result.strip():
            self.left, self.right = "", ""
            return result

        match = self.flank_re.match(result)
        assert match, "This regexp should always match"
        self.left, self.right = match.group(1), match.group(3)
        return match.group(2)