Hello, I am having some confusion about where my `size()`

code will go.

`

```
Balls = []
class Ball:
def __init__(self, x, y, xvel, yvel, radius):
global Balls
self.x = x
self.y = y
self.xvel = xvel
self.yvel = yvel
self.radius = radius
m = radius*.1
self.ball = self
fill(250)
self.drawing = ellipse(x, y, radius, radius)
Balls.append(self)
def update(self):
self.x += xvel
self.y += yvel
def checkWall(self):
if self.x > 640 - self.r:
self.xvel = -self.xvel
if self.x < 0 + self.r:
self.xvel = -self.xvel
if self.y > 480 - self.r:
self.yvel = -self.yvel
if self.y < 0 + self.r:
self.yvel = -self.yvel
draw()
def display(self):
noStroke()
fill(255)
ellipse(self.x, self.y, radius, radius)
def draw():
background(255)
if len(Balls) > 0:
for b in Balls:
b.update()
b.display()
b.checkWall()
def settings():
size(640, 480)
settings()
Ball(100, 100, 20, 10, 50)
Ball(500, 300, 10, 3, 200)`
```

I currently get the error: ’`size()`

cannot be used here.’

Any place `size()`

could go?