Timedelta没有定义

Question

以下是我正在处理的代码.据我所知,没有问题,但当我尝试运行这段代码时,我收到一个错误.

import os 
import datetime

def parseOptions():

    import optparse
    parser = optparse.OptionParser(usage= '-h')
    parser.add_option('-t', '--type', \
                      choices= ('Warning', 'Error', 'Information', 'All'), \
                      help= 'The type of error',
                      default= 'Warning')
    parser.add_option('-g', '--goback', \
                      type= 'string')
    (options, args) = parser.parse_args()
    return options

options = parseOptions() now = datetime.datetime.now() subtract = timedelta(hours=options.goback) difference = now - subtract

if options.type=='All' and options.goback==24:
    os.startfile('logfile.htm')

else: 
    print
    print 'Type =', options.type,
    print
    print 'Go Back =', options.goback,'hours'
    print difference.strftime("%H:%M:%S %a, %B %d %Y")
    print

错误如下:

Traceback (most recent call last):
  File "C:\Python27\Lib\SITE-P~1\PYTHON~2\pywin\framework\scriptutils.py", line 325, in RunScript
    exec codeObject in __main__.__dict__
  File "C:\Users\user\Desktop\Python\python.py", line 19, in <module>
    subtract = timedelta(hours=options.goback)
NameError: name 'timedelta' is not defined

任何帮助,将不胜感激.

Answer 1

您已导入日期时间,但未定义timedelta.你想要:

from datetime import timedelta

要么:

subtract = datetime.timedelta(hours=options.goback)

此外,您的goback参数定义为字符串,但随后将其作为小时数传递给timedelta.您需要将其转换为整数,或者更好地type将选项中的参数设置为int.