size = (100, 200)
width = size[0]

len(size) #2
max(size) #200
min(size) #100
100 in size #true

movement = [5, -2, -3, 4, -1]
first_movement = movement[0] # 5
movement[0] = 7
movement.append(-5) #[7, -2, -3, 4, -1, -5]
movement.remove(-3) #[7, -2, 4, -1, -5]

starting_positions = {'p_0': 50, 'p_1': 100, 'p_2': 150}
starting_positions['p_0'] #50
starting_positions.keys()
starting_positions.values())
