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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 _sra_download_worker(*args):
 """A worker to download SRA files. To be used with multiprocessing. """

    gsm = args[0][0]
    email = args[0][1]
    dirpath = args[0][2]
    kwargs = args[0][3]
    return (gsm.get_accession(), gsm.download_SRA(email, dirpath, **kwargs))