A structure to specify a key of the strong keyed hash spec.
The strong hash requires a
key, which is a list of 2 unsigned integer
numbers. These should be non-zero; random numbers generated from random.org
would be a fine choice.
key: The key to be used by the keyed hashing function.
@staticmethod __new__( cls, key )
Create new instance of HasherSpec(hasher, key)