IndexError at /xadmin/trade/shoppingcart/add/
list index out of range
Request Method:	GET
Request URL:	http://127.0.0.1:8000/xadmin/trade/shoppingcart/add/
Django Version:	1.11.16
Exception Type:	IndexError
Exception Value:	
list index out of range
Exception Location:	/Users/lmy/Desktop/MAX/MAX/extra_apps/xadmin/widgets.py in render, line 85
Python Executable:	/Users/lmy/Desktop/web/MAX/bin/python
Python Version:	3.6.7
Python Path:	
['/Users/lmy/Desktop/MAX/MAX/extra_apps',
 '/Users/lmy/Desktop/MAX/MAX/apps',
 '/Users/lmy/Desktop/MAX/MAX',
 '/Users/lmy/Desktop/MAX/MAX',
 '/Library/Frameworks/Python.framework/Versions/3.6/lib/python36.zip',
 '/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6',
 '/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/lib-dynload',
 '/Users/lmy/Desktop/web/MAX/lib/python3.6/site-packages',
 '/Users/lmy/Desktop/web/MAX/lib/python3.6/site-packages/setuptools-39.1.0-py3.6.egg']
Server time:	星期日, 2 十二月 2018 22:32:10 +0800

怎么办呢？

'</i></span>%s<span class="input-group-btn"><button class="btn btn-default" type="button">%s</button></span></div></div>' % (input_html[0], _(u'Today'), input_html[1], _(u'Now')))

应该是后面的语法错误 ，添加时间的项目出错
求解答！