Dear All , i am making an E-learning application and am using auth.user.first_name but when i logout an error happens :
<type 'exceptions.AttributeError'>('NoneType' object has no attribute 'first_name') this is the controller : def index(): """ example action using the internationalization operator T and flash rendered by views/default/index.html or views/generic.html """ meterials=db().select(db.addmaterial.ALL) metforteacher=db(db.addmaterial.techer==auth.user.first_name).select(db.addmaterial.ALL) return dict(meterials=meterials,metforteacher=metforteacher) what is happening ??