def create_lookup_tables(unique_words):
    
    """ Create lookup tables for word_to_id and id_to_word
    
    Args:
        unique_words: dictionary of words in training set
    
    Return:
        word_to_id: dict with words as keys and corresponding ids as values
        id_to_word: dict with ids as keys and corresponding words as values
    """
    
    word_to_id = {}  # word->id lookup
    id_to_word = {}  # id->word lookup
    for index, word in enumerate(sorted(list(unique_words))):
        word_to_id[word] = index + 1
        id_to_word[index + 1] = word
    return word_to_id, id_to_word