Python: How to update value of key value pair in nested dictionary?

Question

i am trying to make an inversed document index, therefore i need to know from all unique words in a collection in which doc they occur and how often.

i have used this an

Answer 1

It would be better to kick AutoVivification out all together, because it adds nothing.

The following line:

if (word == keyword and dictionary[keyword][filename] is not None):

Doesn't work as expected, because of the way your class works, dictionary[keyword] will always return an instance of AutoVivification, and so will dictionary[keyword][filename].