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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 _fastfood_build(args):
 """Run on `fastfood build`."""

    written_files, cookbook = food.build_cookbook(
        args.config_file, args.template_pack,
        args.cookbooks, args.force)

    if len(written_files) > 0:
        print("%s: %s files written" % (cookbook,
                                        len(written_files)))
    else:
        print("%s up to date" % cookbook)

    return written_files, cookbook