input: def vowelCheck(inputString: str) -> str: 
      """ Detects the first vowel in a given string. If no vowel is found, it returns an empty string.
      >>> vowelCheck("Hello World")
      'e'
      >>> vowelCheck("rhythm")
      ''
      >>> vowelCheck("")
      ''
      >>> vowelCheck("Apple")
      'A'
      """
      vowels = ['a','e','i','o','u','A','E','I','O','U'] 
      for x in inputString: 
          if x in vowels: 
              return x
output:     return ''