code: def recommendForAllUsers(self, numItems):
      return self._call_java("recommendForAllUsers", numItems)
  
imports: import sys
  from synapse.ml.recommendation._RankingTrainValidationSplitModel import _RankingTrainValidationSplitModel
  from pyspark.ml.util import *
label_desc: Use image node_id 1 for calling the RankingTrainValidationSplitModel obj's underlying member method code with example usage: obj.recommendForAllUsers(numItems) and returns: self