def METHOD_NAME(self, char_list):
    char_list.sort()
    i = 0
    n = len(char_list)
    result = []
    while i < n:
        c1 = ord(char_list[i])
        c2 = c1
        i += 1
        while i < n and ord(char_list[i]) == c2 + 1:
            i += 1
            c2 += 1
        result.append((chr(c1), chr(c2)))
    return tuple(result)