'cons(i) is TRUE <=> b[i] is a consonant.'

def cons(self, i):

    if ((self.b[i] == 'a') or (self.b[i] == 'e') or (self.b[i] == 'i') or (self.b[i] == 'o') or (self.b[i] == 'u')):
        return 0
    if (self.b[i] == 'y'):
        if (i == self.k0):
            return 1
        else:
            return (not self.cons((i - 1)))
    return 1
