Error in custom action

Hi i am working on faq chatbot and i am getting this error can you help me please with that:

the bot answers just for greetting and goodbye when the intent is 'inform ’ it’s give the error above. and when i run rasa shell --debug i got this: here is my actions.py:

i will really appreciate your help!thank you

Try also running the action server with --debug, maybe this can help you find the exception.