beats[p2] == p[1] means vise-versa. If player2, nor player1 cant win, then its draw lol

But the second one also which says beats[p2] == [p1] gives the same value, where key beats value always, the how will player 2 win?

I had a hard time to understand this so i will try to explain for the poeple, who had a question like me.
results = ['Draw!', 'Player 1 won!', 'Player 2 won!']
the first item in the arrays has index [0], the second has index[0] etc but when its negative its go backwards like
'Player 2 won!' is [-1], 'Player 1 won!' is [-2] and finally 'Draw!' is [-3].
[-0] is same as [0]