code: def set_init_score(self, init_score):
          
          self.init_score = init_score
          if self.handle is not None and init_score is not None:
              init_score = list_to_1d_numpy(init_score, np.float64, name='init_score')
              self.set_field('init_score', init_score)
          return self
docs: Set init score of Booster to start from.
  
          Parameters
          ----------
          init_score : list, numpy 1-D array, pandas Series or None
              Init score for Booster.
  
          Returns
          -------
          self : Dataset
              Dataset with set init score.