input: Write a function to filter out all the vowels from a given string and return the resulting string without vowels. If the input string is empty, return an empty string.
  def filter_vowels(string):
       vowels = ('a', 'e', 'i', 'o', 'u')
       return ''.join(c for c in string if c not in vowels)
  assert filter_vowels("Hello World") == "Hll Wrld"
  assert filter_vowels("Python Programming") == "Pythn Prgrmmng"
  assert filter_vowels("AEIOUaeiou") == ""
  assert filter_vowels("") == ""
output: def filter_vowels(string):
       vowels = ('a', 'e', 'i', 'o', 'u', 'A', 'E', 'I', 'O', 'U')
       return ''.join(c for c in string if c not in vowels)