Class variables
The following input fails for all languages
```py
class A:
  B = 'FOO'

if __name__ == '__main__':
	assert A.B == 'FOO'
	print('OK')
```

The following Rust is generated
```rust
struct A {
B: ST0,
}

impl A {
let B: &str = "FOO";
}
fn main()  {
assert!(A::B == "FOO");
println!("{}","OK");
}
```

When we know `B` is not mutated, it could be a `const` in Rust.  mutable class variables require a shadow struct with a module level global/static instance, and getter/setters in the instance struct.
