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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_to_submit_args(s):
 """Adds string s to the PYSPARK_SUBMIT_ARGS env var"""

    new_args = os.environ.get("PYSPARK_SUBMIT_ARGS", "") + (" %s" % s)
    os.environ["PYSPARK_SUBMIT_ARGS"] = new_args
    return new_args