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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 copy_plus(orig, new):
 """Copy a fils, including biological index files. """

    for ext in ["", ".idx", ".gbi", ".tbi", ".bai"]:
        if os.path.exists(orig + ext) and (not os.path.lexists(new + ext) or not os.path.exists(new + ext)):
            shutil.copyfile(orig + ext, new + ext)