Then I have a BSP struct that looks like this:
```
pub struct Ui {
    io_expander: Aw9523b<I2cDeviceOnSharedBus>,
}
```
The question would be, how can I name `E` in my impl for `Ui`?
```
impl<E> Ui
where
    embedded_hal_async::i2c::I2c<Error = E>,
{
    pub async fn initialize(&mut self) -> Result<(), Error<E>> {
        // Stuff
    }
}
```