def swap_letter(word):
    last = last_char(word)
    pos = (np.random.randint((last - 2)) + 1)
    return (((word[:pos] + word[(pos + 1)]) + word[pos]) + word[(pos + 2):])
def swap_letter(word):
    last = last_char(word)
    pos = (np.random.randint((last - 2)) + 1)
    return (((word[:pos] + word[(pos + 1)]) + word[pos]) + word[(pos + 2):])