Type Alias MyMap 

pub type MyMap<T: Config> = StorageMap<_GeneratedPrefixForStorageMyMap<T>, Blake2_128Concat, u32, u64>;

Define a storage item to illustrate multi-block migrations.

Storage type is [StorageMap] with key type u32 and value type u64.

Aliased Type

pub struct MyMap<T: Config>(/* private fields */);