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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def json_tuple(col, *fields):
 """Creates a new row for a json column according to the given field names. :param col: string column in json format :param fields: list of fields to extract [Row(key=u'1', c0=u'value1', c1=u'value2'), Row(key=u'2', c0=u'value12', c1=None)] """

    sc = SparkContext._active_spark_context
    jc = sc._jvm.functions.json_tuple(_to_java_column(col), _to_seq(sc, fields))
    return Column(jc)