input: Write a function to identify the words that contain more than one vowel in a given sentence. Return a list of such words. If no such words exist, return an empty list. If the sentence is empty, return an empty list.
  
  import re
  
  assert contains_multiple_vowels("The quick brown fox jumped over the lazy dog.") == ['quick', 'brown', 'jumped', 'over', 'lazy']
  assert contains_multiple_vowels("Hello world") == ['Hello', 'world']
  assert contains_multiple_vowels("Python is fun") == []
  assert contains_multiple_vowels("") == []
  assert contains_multiple_vowels("Sky is blue and earth is vast") == ['blue', 'vast']
output: def contains_multiple_vowels(sentence):
      if not sentence:
          return []
      words = sentence.split()
      vowels = set('aeiouAEIOU')
      result = []
      for word in words:
          vowel_count = sum(1 for char in word if char in vowels)
          if vowel_count > 1:
              result.append(word)
      return result