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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

FIX = """Add more test cases."""
def vowels_count(s):
    """Write a function vowels_count which takes a string representing
    a word as input and returns the number of vowels in the string.
    Vowels in this case are 'a', 'e', 'i', 'o', 'u'. Here, 'y' is also a
    vowel, but only when it is at the end of the given word.

    Example:
    >>> vowels_count("abcde")
    2
    >>> vowels_count("ACEDY")
    3
    """
    vowels = "aeiouAEIOU"
    n_vowels = sum(c in vowels for c in s)
    if s[-1] == 'y' or s[-1] == 'Y':
        n_vowels += 1
    return n_vowels
