#!/usr/bin/env python3
# -*- coding: UTF-8 -*-
import re
a = 'java*&39android##@@python'
# 数量词
findall = re.findall('[a-z]{4,7}', a)
print(findall)
# 贪婪与非贪婪
re_findall = re.findall('[a-z]{4,7}?', a)
print(re_findall)