input: Write a function to detect if a given character in a string is a vowel. If it is a vowel, return the vowel; otherwise, return False.
  assert vowelCheck("Hello World")=="e"
  assert vowelCheck("Python")==False
  assert vowelCheck("AbcdEf")=="A"
  assert vowelCheck("Junior")=="u"
  assert vowelCheck("Goodbye")==False
output: def vowelCheck(s):
      vowels = "aeiouAEIOU"
      for char in s:
          if char in vowels:
              return char
      return False