code: def hash(*cols):
      
      sc = SparkContext._active_spark_context
      jc = sc._jvm.functions.hash(_to_seq(sc, cols, _to_java_column))
      return Column(jc)
docs: Calculates the hash code of given columns, and returns the result as an int column.
  
      >>> spark.createDataFrame([('ABC',)], ['a']).select(hash('a').alias('hash')).collect()
      [Row(hash=-757602832)]