code: public TrieBuilder<T> set(String word, T value) {
          assertNotEmptyWord(word);
  
          // Save the word-value pair in the map. The actual construction will be done later.
          map.put(word, value);
          return this;
      }
docs: Set a word-value mapping on the Trie. If a previous mapping exists, it will be overwritten.
  Otherwise, will create a new word-value mapping.
  
  @param word The word for the word-value mapping.
  @param value The value for the word-value mapping.
  @return {@code this}, for chaining.