def get_count(input_str: str) -> int:
    """Count vowel from input string.

    Args:
        input_str: <str> inout string.

    Returns: <int> total amount of vowels.

    Examples:
        >>> assert get_count('abracadabra') == 5

    """
    return sum(map(lambda letter: letter in 'aeiou', input_str))