def omission(word, num_omit=1):
    last = last_char(word)
    for i in range(num_omit):
        omit = (np.random.randint((last - 1)) + 1)
        word = (word[:omit] + word[(omit + 1):])
        last -= 1
    return word
def omission(word, num_omit=1):
    last = last_char(word)
    for i in range(num_omit):
        omit = (np.random.randint((last - 1)) + 1)
        word = (word[:omit] + word[(omit + 1):])
        last -= 1
    return word