input: Write a python function to extract features from a sentence using a given list of word features.
  assert extract_features("This is a great day for a walk.") == {'this': True, 'is': True, 'a': True, 'great': True, 'day': True, 'for': True, 'walk.': True, 'today\'s': False, 'forecast': False, 'looks': False, 'horrible': False, 'the': False, 'weather': False, 'so': False, 'beautiful.': False}
  assert extract_features("Today's forecast looks horrible") == {'this': False, 'is': False, 'a': False, 'great': False, 'day': False, 'for': False, 'walk.': False, 'today\'s': True, 'forecast': True, 'looks': True, 'horrible': True, 'the': False, 'weather': False, 'so': False, 'beautiful.': False}
  assert extract_features("The weather is so beautiful.") == {'this': False, 'is': True, 'a': False, 'great': False, 'day': False, 'for': False, 'walk.': False, 'today\'s': False, 'forecast': False, 'looks': False, 'horrible': False, 'the': True, 'weather': True, 'so': True, 'beautiful.': True}
output: def extract_features(sentence):
      word_features = ["this", "is", "a", "great", "day", "for", "walk.", "today's", "forecast", "looks", "horrible", "the", "weather", "so", "beautiful."]
      words = sentence.lower().split()
      return {word: word in words for word in word_features}