NameError: global name 'numbers_t' is not defined

def addExample(self, klass, words):
    """
     * TODO
     * Train your model on an example document with label klass ('pos' or 'neg') and
     * words, a list of strings.
     * You should store whatever data structures you use for your classifier 
     * in the NaiveBayes class.
     * Returns nothing
    """
    #numbers_t = (0,)*3
    #numbers_t_sum = (0,)*3
    self.count_docs += 1
    for word in words:
       if word not in self.vocab:
            self.vocab.append(word)

    if klass == 'pos':
        self.num_pos += 1
        self.docs_pos.append(words)    
    if klass == 'neg':
        self.num_neg += 1
        self.docs_neg.append(words)
    
    for t in self.vocab:
        self.condprob_pos = math.log(numbers_t(self.vocab, self.docs_pos) + 1) - math.log(self.numbers_t_sum(self.vocab, self.docs_pos) + len(self.vocab))
        
    for t in self.vocab:
        self.condprob_neg = math.log(numbers_t(self.vocab, self.docs_neg) + 1) - math.log(self.numbers_t_sum(self.vocab, self.docs_neg) + len(self.vocab))
    
    pass
    
  def numbers_t(self, a, b):
    for t in a:
        for word in b:
            if t == b:
                result += 1  
    return result
      
  def numbers_t_sum(self, a, b):
    for t in a:
        for word in b:
            if t == b:
                result += 1
    sum += result
    return sum