程式碼示例：

# 匹配數字或字母

import re

rc = re.compile(r"""
# start a rule

/d+
# number

| 

[a-zA-Z]+
# word

""", re.X)
res = rc.match('aaaa')
# print(res)
print(res.group())


執行結果:
F:\win10software\Python36\python36.exe
aaaa

Process finished with exit code 0



# 匹配空格

import re

rc = re.compile(r"""
# 開始匹配規則
# 匹配一個或多個空格，也可以用"\s+"代替
\  +

""", re.X)
res = rc.match('   11')  # 字串包含三個空格
print(res)
print('='*30)
print('=%s=' % res.group())

# 執行結果
F:\win10software\Python36\python36.exe
<_sre.SRE_Match object; span=(0, 3), match='   '>
==============================
=   =

Process finished with exit code 0