screen = turtle.Screen()
screen.bgcolor("black")

def create_firework():
    colors = ["red", "orange", "yellow", "green", "blue", "purple", "white"]
    firework = turtle.Turtle()
    firework.shape("circle")
    firework.color(random.choice(colors))
    firework.shapesize(0.5)
    firework.penup()
    firework.speed(0)
    firework.goto(random.randint(-200, 200), -200)
......................