vowels.py

def has_vowel(s):
    """(str) -> bool
    Return True if and only if s has at least one vowel, not including y.
    >>> has_vowel("Anniversary")
    True
    >>> has_vowel("xyz")
    False
    """
    vowel_found = False
    for char in s:
        if char in 'aeiouAEIOU':
            vowel_found = True
        
    return vowel_found











def collect_vowels (s):
    '''(str) -> str
    Return the vowels from s. Do not treat
    y as a vowel.
    
    >>>collect_vowels ('Happy Anniversary!')
    'aAiea'
    >>>collect_vowels ('xyz')
    '''
    vowels = ''
    for char in s:
        if char in 'aeiuoAEIUO':
            vowels = vowels + char
    return vowels

            
            



def count_vowels (s):
    '''(str)-> int
    
    rturn the vowels in s.Do not treat y as a vowel.
    >>>count_vowels('Happy aniversary!')
    5
    >>>count_vowels ('xyz')
    0
    '''
    num_vowels = 0
    for char in s:
        if char in 'aeiuoAEIUO':
            num_vowels = num_vowels + 1
    return num_vowels