def get_feature_names(self):
    self.feature_names = []
    for param_dict in self.param_dict:
        (key, var, agg, on) = self._get_params(param_dict)
        self.feature_names += self._get_feature_names(key, var, agg)
    return self.feature_names
def get_feature_names(self):
    self.feature_names = []
    for param_dict in self.param_dict:
        (key, var, agg, on) = self._get_params(param_dict)
        self.feature_names += self._get_feature_names(key, var, agg)
    return self.feature_names