title: Print only vowels in a string
body: <p>I am new in Python and I'm trying to print all the vowels in a string. So if someone enters "Hey there, everything alright?" , all vowels needs to be printed...but I don't know how? (so it's not about counting the vowels, its about printing the vowels)</p>
  
  <p>For now I've got this ;</p>
  
  <pre><code>sentence = input('Enter your sentence: ' )
  
  if 'a,e,i,o,u' in sentence:
      print(???)
  
  else:
      print("empty")
  </code></pre>