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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 _validate_feature_format(self, feature_format):
 """Validates feature format, raising error if invalid."""


        if feature_format not in self.valid_feature_formats:
            raise InvalidFeatureFormatError(
                "{} is not a valid feature format".format(feature_format)
            )

        return feature_format