input: from typing import List
  
  def count_vowels(string: str) -> int:
      """ Counts the total number of vowels in the given string.
      >>> count_vowels("hello")
      2
      >>> count_vowels("world")
      1
      """
output:     vowels = "aeiouAEIOU"
      count = 0
      for char in string:
          if char in vowels:
              count += 1
      return count