code: func (t *SecureTrie) TryDelete(key []byte) error {
  	hk := t.hashKey(key)
  	delete(t.getSecKeyCache(), string(hk))
  	return t.trie.TryDelete(hk)
  }
docs: // TryDelete removes any existing value for key from the trie.
  // If a node was not found in the database, a MissingNodeError is returned.