Oh of course, thanks for the reminder!
```go
type Shape interface {
Shape()
}
type BaseShape struct {
X int
Y int
PenColor color
PenWidth int
FillColor color
}
type BoxShape struct {
BaseShape
Width int
Height int
}
func (me *BoxShape) Shape() {}
type LineShape struct {
BaseShape
X2 int
Y2 int
}
func (me *LineShape) Shape() {}
shapes := []Shape{}
```
Thank you again.