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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 _regressors(self):
 """ Get a set of supported regressors. Returns ------- regressors : {set} The set of supported regressors. """


        # sklearn version < 0.18.0
        regressors = ()

        # sklearn version >= 0.18.0
        if self.sklearn_ver[:2] >= (0, 18):
            from sklearn.neural_network.multilayer_perceptron \
                import MLPRegressor
            regressors += (MLPRegressor, )

        return regressors