input: 
  def filter_vowels(string: str) -> str:
      """Returns a new string with all the vowels removed from the given string.
      >>> filter_vowels("hello world")
      'hll wrld'
      >>> filter_vowels("python is fun")
      'pythn s fn'
      """
      vowels = ('a', 'e', 'i', 'o', 'u')
      return ''.join(c for c in string if c not in vowels)
  
output:     vowels = ('a', 'e', 'i', 'o', 'u', 'A', 'E', 'I', 'O', 'U')
      return ''.join(c for c in string if c not in vowels)