Python统计文件中去重后uuid个数的方法

import re
pattern=re.compile(r'&uuid=.*&')
uuidset=set()
with open('request.log.2015-05-26','rt') as f:
    for line in f:
        all=pattern.findall(line)
        if len(all)>0 and line.find('iphone')>0:
            # print(all[0])
            uuidset.add(all[0])
print(len(uuidset))