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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 determine_master(port=4000):
 """Determine address of master so that workers can connect to it. If the environment variable SPARK_LOCAL_IP is set, that address will be used. :param port: port on which the application runs :return: Master address Example usage: SPARK_LOCAL_IP=127.0.0.1 spark-submit --master \ local[8] examples/mllib_mlp.py """

    if os.environ.get('SPARK_LOCAL_IP'):
        return os.environ['SPARK_LOCAL_IP'] + ":" + str(port)
    else:
        return gethostbyname(gethostname()) + ":" + str(port)