未完成
参考链接

re.sub使用

• re是regular expression的所写，表示正则表达式；sub是substitute的所写，表示替换。

re.sub(pattern, repl, string, count=0, flags=0)

• pattern是正则表达式模板，eg："$p(?P<delta_days>\d+)d"
• repl是替换的字符，也可以是替换规则的函数
• count是替换的次数，默认全部替换
• flags是一些参数，eg：flags=re.I表明忽略大小写

import re
input = "hello, lockeCucumber"
output = re.sub(r"locke\w+ber", "lucy", input)
print output  # hello, lucy

re.sub参数repl使用函数

def _trans_to_date(matched):
        delta_days = int(matched.group("delta_days"))
        today = dtime.date.today()
        date = today - dtime.timedelta(delta_days)
        return "'{}'".format(str(date))

before_sql = "SELECT intersect_count(a, b, [$p0d, $p1d, $p2d] AS count_id FROM s"
sql = re.sub("\$p(?P<delta_days>\d+)d", _trans_to_date, sql)

print sql # SELECT intersect_count(a, b, ['2018-06-17', '2018-06-16', '2018-06-15'] AS count_id FROM slices

re中match，group的简单使用

根据写过的代码改个例子，具体理论后续补充吧

input = "lockeCucumber.[lucy]"
m = re.match(r"lockeCucumber\.\[(?P<person>\w+)\]", input)
if m:
    love_person = m.group('person')
    print love_person # lucy