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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 same_run_eval(black_num=0, white_num=0, completions=4):
 """Shorthand to spawn a job matching up two models from the same run, identified by their model number """

    if black_num <= 0 or white_num <= 0:
        print("Need real model numbers")
        return

    b = fsdb.get_model(black_num)
    w = fsdb.get_model(white_num)

    b_model_path = os.path.join(fsdb.models_dir(), b)
    w_model_path = os.path.join(fsdb.models_dir(), w)
    flags_path = fsdb.eval_flags_path()

    obj = launch_eval_job(b_model_path + ".pb",
                           w_model_path + ".pb",
                           "{:d}-{:d}".format(black_num, white_num),
                           bucket_name=flags.FLAGS.bucket_name,
                           flags_path=flags_path,
                           completions=completions)

    # Fire spams the retval to stdout, so...
    return "{} job launched ok".format(obj[1].metadata.name)