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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 adjust(self):
 """ If one of the transformations is not defined it is expected to be the mirror image of the other. """


        if self._fro is None and self._to is not None:
            self._fro = dict(
                [(value.lower(), key) for key, value in self._to.items()])
        if self._to is None and self._fro is not None:
            self._to = dict(
                [(value.lower(), key) for key, value in self._fro.items()])