Error message for MACS
 

I tried to run MACS, but I got error message like this,who can tell me how to fix it?

Traceback (most recent call last):
File "/share/biosoft/bin/macs14", line 320, in <module>
main()
File "/share/biosoft/bin/macs14", line 48, in main
options = opt_validate(prepare_optparser())
File "/share/biosoft/software/python/Python-2.6.4/lib/python2.6/site-packages/MACS14/OptValidator.py", line 143, in opt_validate
if options.keepduplicates != "auto" and options.keepduplicates != "all":
AttributeError: Values instance has no attribute 'keepduplicates'