Python查找相似单词的方法

from itertools import tee,izipfrom collections import defaultdictdef pairwise(iterable):  a, b = tee(iterable)  for elem in b:    break  return izip(a, b)buf_array=[]buf_no={}key_from_id=0def add_to_buf(word):  global key_from_id,buf_array  if len(word)==1:    pass    #TODO  for pos,pair in enumerate(pairwise(word)):    if len(buf_array)<pos+1:      buf_array.append(defaultdict(set))    pos_dict=buf_array[pos]    key=list(pair)    key.sort()    key="".join(key)    if key not in buf_no:      buf_no[key]=key_from_id      key_from_id+=1    key=buf_no[key]    pos_dict[key].add(word)def find_in_buf(word):  global key_from_id,buf_array  if len(word)==1:    pass    #TODO  exist = []  for pos,pair in enumerate(pairwise(word)):    if len(buf_array)<pos+1:      return      pos_dict=buf_array[pos]    key=list(pair)    key.sort()    key="".join(key)    if key not in buf_no:      continue    key=buf_no[key]    if key not in pos_dict:      continue    exist.append(pos_dict[key])  count_dict=defaultdict(int)  for i_set in exist:    for i in i_set:      count_dict[i]+=1  result=[]  min_match = len(word)-3  for k,v in count_dict.iteritems():    if v>=min_match:      result.append(k)  return resultadd_to_buf("1234")add_to_buf("ABCD")add_to_buf("CABD")print find_in_buf("ACBD")