def load_words(file_name: str) -> list:
    """Depending on the size of the word list, this function may take a while
    to finish.

    Args:
        file_name: the name of the file containing the list of words to load

    Returns:
        list: a list of valid words. Words are strings of lowercase letters.
    """
    print('Loading word list from file...')
    # inFile: file
    in_file = open(file_name, 'r')
    # line: string
    line = in_file.readline()
    # word_list: list of strings
    word_list = line.split()
    print('  ', len(word_list), 'words loaded.')
    in_file.close()
    return word_list