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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 hash(*cols):
 """Calculates the hash code of given columns, and returns the result as an int column. [Row(hash=-757602832)] """

    sc = SparkContext._active_spark_context
    jc = sc._jvm.functions.hash(_to_seq(sc, cols, _to_java_column))
    return Column(jc)