I am stuck in Rock Paper Scissors Machine Learning Project:

I am using “win-stay,lose_shift” strategy to complete the project but the winning percentage is lower than it should be. Can someone tell me what I’m doing wrong or what should I change.

def player(prev_play,my_history = []):
    winning_set = { 
      "R":"P",
      "P":"S",
      "S":"R"
    }
    if len(my_history)>1:
      if (winning_set[my_history[-1]]==prev_play):
        guess = winning_set[prev_play]
      else:
        guess = winning_set[my_history[-1]]
    else:
      guess = "P"
    my_history.append(guess)
    return guess

Here is a link to challenge.

The 4 opponents employ different strategies. You can see how they act by looking at their functions.