Macro hash 

macro_rules! hash {
    ($str:literal $(,)?) => { ... };
}

Easily create a hash from a hex-encoded literal string. Useful for testing.

Requires:

• hex

Usage:

```

let my_hash32: Hash<32> = hash!(“a7c4477e9fcfd519bf7dcba0d4ffe35a399125534bc8c60fa89ff6b50a060a7a”),

let my_hash28: Hash<28> = hash!(“a7c4477e9fcfd519bf7dcba0d4ffe35a399125534bc8c60fa89ff6b5”),

```