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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 move_to_output_dir(work_dir, output_dir, uuid=None, files=list()):
 """ Moves files from work_dir to output_dir Input1: Working directory Input2: Output directory Input3: UUID to be preprended onto file name Input4: list of file names to be moved from working dir to output dir """

    for fname in files:
        if uuid is None:
            shutil.move(os.path.join(work_dir, fname), os.path.join(output_dir, fname))
        else:
            shutil.move(os.path.join(work_dir, fname), os.path.join(output_dir, '{}.{}'.format(uuid, fname)))