very basic.started learning python only 3 days ago.Kind of frustrating when code doesn't run :     def calculate_average(runs,games):
        runs_list = [5, 7, 3, 1, 4]
        num_games = len(runs_list)
        total_runs=0
        for runs in runs_list:
                total_runs += runs
        return total_runs/num_games
        
    print(calculate_average(runs, num_games))

This gives me an error saying"runs is not defined".I don't get it.Again I am a newbie.I knew it is a steep learning curve.