You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: complex_non_packed_enum.rs
    path of file: ./repos/ink/crates/ink/tests/ui/storage_item/pass
    
    the code of the file until where you have to start completion: use ink_prelude::vec::Vec;
use ink_primitives::KeyComposer;
use ink_storage::{
    traits::{
        AutoKey,
        StorageKey,
    },
    Lazy,
    Mapping,
};

#[derive(Default)]
#[cfg_attr(feature = "std", derive(ink::storage::traits::StorageLayout))]
#[ink::scale_derive(Encode, Decode, TypeInfo)]
enum Packed {
    #[default]
    None,
    A(u8),
    B(u16),
    C(u32),
    D(u64),
    E(u128),
    F(String),
    G {
        a: u8,
        b: String,
    },
    H((u16, u32)),
}

#[ink::storage_item]
#[derive(Default)]
enum NonPacked<KEY: StorageKey = AutoKey> {
    #[default]
    None,
    A(Mapping<u128, Packed>)
    
fn main() {
    ink_env::test::run_test::<ink_env::DefaultEnvironment, _>(|_| {
        let mut contract = Contract::default();
        assert_eq!(contract.key(), 0);

        // contract.a
        assert_eq!(contract.a.key(), KeyComposer::from_str("Contract::a"));
        assert_eq!(
            contract.a.get_or_default().key(),
            KeyComposer::from_str("Contract::a"),
        );

        contract.a.set(&NonPacked::<_>::A(Default::default()));
        let variant = if let Some(NonPacked::<_>::A(variant)) = contract.a.get() {
            variant
        } else {
            panic!("Wrong variant")
        };
        assert_eq!(
            variant.key(),
            KeyComposer::concat(
                KeyComposer::from_str("NonPacked::A::0"),
                KeyComposer::from_str("Contract::a")
            ),
        );

        contract.a.set(&NonPacked::<_>::B(Default::default()));
        let variant = if let Some(NonPacked::<_>::B(variant)) = contract.a.get() {
            variant
        } else {
            panic!("Wrong variant")
        };
        assert_eq!(
            variant.key(),
            KeyComposer::concat(
                KeyComposer::from_str("NonPacked::B::0"),
                KeyComposer::from_str("Contract::a")
            ),
        );

        contract.a.set(&NonPacked::<_>::C(Default::default()));
        let variant = if let Some(NonPacked::<_>::C(variant)) = contract.a.get() {
            variant
        } else {
            panic!("Wrong variant")
        };
        assert_eq!(
            variant.key(),
            KeyComposer::concat(
                KeyComposer::from_str("NonPacked::C::0"),
                KeyComposer::from_str("Contract::a")
            ),
        );

        contract.a.set(&NonPacked::<_>::D(Default::default()));
        let variant = if let Some(NonPacked::<_>::D(variant)) = contract.a.get() {
            variant
        } else {
            panic!("Wrong variant")
        };
        assert_eq!(
            variant.key(),
            KeyComposer::concat(
                KeyComposer::from_str("NonPacked::D::0"),
                KeyComposer::from_str("Contract::a")
            ),
        );

        contract.a.set(&NonPacked::<_>::E(Default::default()));
        let variant = if let Some(NonPacked::<_>::E(variant)) = contract.a.get() {
            variant
        } else {
            panic!("Wrong variant")
        };
        assert_eq!(
            variant.key(),
            KeyComposer::concat(
                KeyComposer::from_str("NonPacked::E::0"),
                KeyComposer::from_str("Contract::a")
            )
        );

        contract.a.set(&NonPacked::<_>::F {
            a: Default::default(),
        });
        let variant = if let Some(NonPacked::<_>::F { a }) = contract.a.get() {
            a
        } else {
            panic!("Wrong variant")
        };
        assert_eq!(
            variant.key(),
            KeyComposer::concat(
                KeyComposer::from_str("NonPacked::F::a"),
                KeyComposer::from_str("Contract::a")
            )
        );
        Ok(())
    })
    .unwrap()
}