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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 rstrip_extra(fname):
 """Strip extraneous, non-discriminative filename info from the end of a file. """

    to_strip = ("_R", ".R", "-R", "_", "fastq", ".", "-")
    while fname.endswith(to_strip):
        for x in to_strip:
            if fname.endswith(x):
                fname = fname[:len(fname) - len(x)]
                break
    return fname