I have a function that draw an image on graphics:

```
private void DrawSmallImage(Graphics g)
{
            if (this.SmallImage == null) return; 

            var smallPicHeight = this.Height / 5;

            var x = this.ClientSize.Width - smallPicHeight;
            var y = this.ClientSize.Height - smallPicHeight;

            g.DrawImage(this.SmallImage, x, y, smallPicHeight, smallPicHeight);
 }

```

the check `if (this.SmallImage == null) return;` should be in the function DrawSmallImage or should be in the caller? which is better?