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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 set_reference(self, reference):
 """Set reference Dataset. Parameters reference : Dataset Reference that is used as a template to construct the current Dataset. Returns ------- self : Dataset Dataset with set reference. """

        self.set_categorical_feature(reference.categorical_feature) \
            .set_feature_name(reference.feature_name) \
            ._set_predictor(reference._predictor)
        # we're done if self and reference share a common upstrem reference
        if self.get_ref_chain().intersection(reference.get_ref_chain()):
            return self
        if self.data is not None:
            self.reference = reference
            return self._free_handle()
        else:
            raise LightGBMError("Cannot set reference after freed raw data, "
                                "set free_raw_data=False when construct Dataset to avoid this.")