Load the term_freq from spell_file

def load_spelling(spell_file=SPELLING_FILE):
    """
    Load the term_freq from spell_file
    """
    with open(spell_file) as f:
        tokens = f.read().split('\n')
        size = len(tokens)
        term_freq = {token: size - i for i, token in enumerate(tokens)}
    return term_freq