python：从任意格式的时间转换为Unix时间戳（Unix timestamp）

Unix timestamp：是从1970年1月1日（UTC/GMT的午夜）开始所经过的秒数，不考虑闰秒。

以25/Jul/2012:13:26:58为例

python程序：

import time

import datetime

x = datetime.datetime.strptime('25/Jul/2012:13:26:58', '%d/%b/%Y:%H:%M:%S')

time.mktime( x.timetuple() )  

输出：

1343194018.0

注：

strptime函数中时间字符串的格式化说明：

%a Abbreviated weekday name
%A Full weekday name
%b Abbreviated month name
%B Full month name
%c Date and time representation appropriate for locale
%d Day of month as decimal number (01 - 31)
%H Hour in 24-hour format (00 - 23)
%I Hour in 12-hour format (01 - 12)
%j Day of year as decimal number (001 - 366)
%m Month as decimal number (01 - 12)
%M Minute as decimal number (00 - 59)
%p Current locale's A.M./P.M. indicator for 12-hour clock
%S Second as decimal number (00 - 59)
%U Week of year as decimal number, with Sunday as first day of week (00 - 51)
%w Weekday as decimal number (0 - 6; Sunday is 0)
%W Week of year as decimal number, with Monday as first day of week (00 - 51)
%x Date representation for current locale
%X Time representation for current locale
%y Year without century, as decimal number (00 - 99)
%Y Year with century, as decimal number
%z, %Z Time-zone name or abbreviation; no characters if time zone is unknown
%% Percent sign