當我指定一個命令行選項時，GetOpt 似乎不起作用，拋出異常，這個名為 o.py 的文件：import getoptimport sysopts,args = getopt.getopt(sys.argv[1:], "m:p:", ['mode', 'perf'])for opt_name,opt_value in opts:    if opt_name in ('--mode'):        print opt_name        continue    if opt_name in ('--perf'):        print opt_name        continue然后我在以下情況下收到運行時異常：python o.py --mode=aTraceback (most recent call last):File "o.py", line 3, in <module>    opts,args = getopt.getopt(sys.argv[1:], "m:p:", ['mode', 'perf'])File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/getopt.py", line 88, in getopt    opts, args = do_longs(opts, args[0][2:], longopts, args[1:])File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/getopt.py", line 159, in do_longs    raise GetoptError('option --%s must not have an argument' % opt, opt)getopt.GetoptError: option --mode must not have an argumentopts, args = do_longs(opts, args[0][2:], longopts, args[1:])文件 "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/getopt.py", line 159, in do_longs raise GetoptError('option --%s must not have an argument' % opt, opt ) getopt.GetoptError: 選項 --mode 不能有參數那么我哪里出錯了，如何解決呢？