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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 add_months(start, months):
 """ Returns the date that is `months` months after `start` [Row(next_month=datetime.date(2015, 5, 8))] """

    sc = SparkContext._active_spark_context
    return Column(sc._jvm.functions.add_months(_to_java_column(start), months))