code: def get_json_object(col, path):
      
      sc = SparkContext._active_spark_context
      jc = sc._jvm.functions.get_json_object(_to_java_column(col), path)
      return Column(jc)
docs: Extracts json object from a json string based on json path specified, and returns json string
      of the extracted json object. It will return null if the input json string is invalid.
  
      :param col: string column in json format
      :param path: path to the json object to extract
  
      >>> data = [("1", '''{"f1": "value1", "f2": "value2"}'''), ("2", '''{"f1": "value12"}''')]
      >>> df = spark.createDataFrame(data, ("key", "jstring"))
      >>> df.select(df.key, get_json_object(df.jstring, '$.f1').alias("c0"), \\
      ...                   get_json_object(df.jstring, '$.f2').alias("c1") ).collect()
      [Row(key=u'1', c0=u'value1', c1=u'value2'), Row(key=u'2', c0=u'value12', c1=None)]