name 'BoxAPIException' is not defined

My code is sorting and moving the files based on the file type. i am included a try and except block in case the file is already included in the folder, it should move to different folder. But i am getting below error

NameError                                 Traceback (most recent call last)
 in ()
     24 
     25 
---> 26         except BoxAPIException:
     27                 print('possible duplicate')
     28                 print('Copying ' + filesInEachFolder[j].name)

NameError: name 'BoxAPIException' is not defined

 Can someone help me with this issue