code: def merge_pres_feats(pres, features):
      
  
      sub = []
      for psub, fsub in zip(pres, features):
          exp = []
          for pexp, fexp in zip(psub, fsub):
              lst = []
              for p, f in zip(pexp, fexp):
                  p.update(f)
                  lst.append(p)
              exp.append(lst)
          sub.append(exp)
      return sub
docs: Helper function to merge pres and features to support legacy features argument