code: def getOrCreate(cls, sc):
          
          if cls._instantiatedContext is None:
              jsqlContext = sc._jvm.SQLContext.getOrCreate(sc._jsc.sc())
              sparkSession = SparkSession(sc, jsqlContext.sparkSession())
              cls(sc, sparkSession, jsqlContext)
          return cls._instantiatedContext
docs: Get the existing SQLContext or create a new one with given SparkContext.
  
          :param sc: SparkContext