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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 get_file_list(opts):
 """ Returns a list containing file paths of requested files to be parsed using AnchorHub options. :param opts: Namespace containing AnchorHub options, usually created from command line arguments :return: a list of absolute string file paths of files that should be parsed """

    if opts.is_dir:
        # Input is a directory, get a list of files
        return get_files(opts.abs_input, opts.extensions, exclude=[
            opts.abs_output], recursive=opts.recursive)
    elif os.path.isfile(opts.input):
        # Input is a file, should only parse that one file
        return [opts.abs_input]
    else:
        # Input is non-existent
        return []