text: import vineyard
  import mars
  import mars.dataframe as md
  
  vineyard_deployment = vineyard.connect('vineyard-k8s-service')
  
  # this create a default session for mars
  # so that following operations are applied
  # within the scope of the session
  mars.session(vineyard_deployment)
  
  dataset = md.from_vineyard(vineyard.io.open('hdfs://server/data_full'))
  
  df = dataset.dropna().filter(condition).vectorize(method).to_vineyard()
  