input: Write a python program to extract the non-vowel words in a sentence.
  
  def extract_non_vowel_words(sentence):
      non_vowel_words = []
      words = sentence.split()
      vowels = set('aeiouAEIOU')
      for word in words:
          if not any(char in vowels for char in word):
              non_vowel_words.append(word)
      return non_vowel_words
  
  assert extract_non_vowel_words("This machine learning project is challenging.") == ['This', 'machine', 'learning', 'project', 'is', 'challenging']
  assert extract_non_vowel_words("Fly quietly over the yellow moon.") == ['Fly', 'quietly', 'over', 'the', 'moon']
  assert extract_non_vowel_words("Shy velvet brown jar slams!") == ['Shy', 'velvet', 'brown', 'jar', 'slams']
  assert extract_non_vowel_words("") == []
output: def extract_non_vowel_words(sentence):
      non_vowel_words = []
      words = sentence.split()
      vowels = set('aeiouAEIOU')
      for word in words:
          if not any(char in vowels for char in word):
              non_vowel_words.append(word)
      return non_vowel_words