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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 _repr_values(self):
 """Return values that are to be shown in repr string."""

        def getattr_better(obj, field):
            try:
                return getattr(obj, field)
            except AttributeError as e:
                try:
                    return getattr(obj, '_' + field)
                except AttributeError:
                    raise e

        return (getattr_better(self, attr) for attr in self._repr_attributes)