Character-level n-grams that match between two strings

        Args:
            s1: a string
            s2: another string
            n: an int for the n in n-gram

        Returns:
            set: the n-grams found in both strings

def char_matches(s1, s2, n=3):
    """
        Character-level n-grams that match between two strings

        Args:
            s1: a string
            s2: another string
            n: an int for the n in n-gram

        Returns:
            set: the n-grams found in both strings
    """
    return __matches(s1, s2, char_ngrams, n=n)