Why does this hang the system up

[Able98]

It seems to not allow me to do anything else on the desktop. The mouse still moves as it should and that is about it.

Here is what it says

  71         return ""
     72     try:
     73         o = decode_keystore_json(w,pw)
     74         print(o)
     75         # print (pw)q
---> 76         raise PasswordFoundException("MY**") #("""\n\nYour password is:\n%s""" % o)
        
     77     except ValueError as e:
     78         # print(e)
     79         return ""
     80             

NameError: name 'PasswordFoundException' is not defined

I hit control C and it let me close the program once. Other times it would not.