count how many vowels in a string python

1def vowel_count(string):
2  vowels = ['a', 'e', 'i', 'o', 'u']
3  return len([i for i in string if i in vowels])

1vow = ['a', 'A', 'e',
2          'E', 'i', 'I',
3          'o', 'O', 'U',
4          'u', 'Y', 'y']
5
6def vowels(str):
7  
8  global vow
9  string = list(str)
10  count = 0
11  
12  for i in range(len(string)):
13    
14    if string[i] in vow:
15      
16      count += 1
17  return count
18