start-python/pong/paddle.py

from turtle import Turtle
from config import SCREEN_HEIGHT, PADDLE_LENGTH
STEP = 20

class Paddle(Turtle):
    def __init__(self, pos):
        super().__init__()
        self.shape("square")
        self.color("white")
        self.setheading(90)
        self.penup()
        # self.speed("fastest")
        self.shapesize(stretch_len=PADDLE_LENGTH, stretch_wid=1)
        self.goto(pos, 0)

    def up(self):
        y = self.ycor()
        if y < SCREEN_HEIGHT / 2 - PADDLE_LENGTH * 5 - STEP * 2:
            self.forward(STEP)   

    def down(self):
        y = self.ycor()
        if y > -(SCREEN_HEIGHT / 2 - PADDLE_LENGTH * 5 - STEP * 2):
            self.backward(STEP)