Reset the registry to the standard multihash functions.

def reset(cls):
        """Reset the registry to the standard multihash functions."""
        # Maps function names (hyphens or underscores) to registered functions.
        cls._func_from_name = {}

        # Maps hashlib names to registered functions.
        cls._func_from_hash = {}

        # Hashlib compatibility data by function.
        cls._func_hash = {}

        register = cls._do_register
        for (func, hash_name, hash_new) in cls._std_func_data:
            register(func, func.name, hash_name, hash_new)
        assert set(cls._func_hash) == set(Func)