Python - for/break/else - (FB: learnpython.org)

sentence = input("Enter a sentence: ")

keyword = input("Input a keyword from the sentence: ")

words = sentence.split()

for i, word in enumerate(words, 1):
    if keyword.lower() == word.lower():
        print("This word appears (first time) in sentence in position", i)
        # keyword found so leave `for` loop
        break
else: # there was no break
    print("not in sentence")