input: Write a python function to replace vowels in a string with asterisks.
  assert replaceVowels("Hello, World!") == "H*ll*, W*rld!"
  assert replaceVowels("Python Programming") == "Pyth*n Pr*gr*mm*ng"
  assert replaceVowels("AEIOUaeiou") == "**********"
  assert replaceVowels("Testing 123") == "T*st*ng 123"
output: def replaceVowels(s):
      vowels = "AEIOUaeiou"
      return ''.join('*' if char in vowels else char for char in s)