findall 的捕获分组与非捕获分组
# -*- coding:utf-8 -*
import re
str1 = 'fdg@163.com abc@qq.com'
reg_str1=r'([0-9a-zA-Z_]+)+@'# 打印结果 ['fdg', 'abc']
#reg_str1=r'(?:[0-9a-zA-Z_]+)+@'# 打印结果 ['fdg@', 'abc@']
mod = re.compile(reg_str1)
items = mod.findall(str1)
print(items)