pycharm removes whitespaces?

Hi,
I've got dictionary in my code. For it to conform with pylint of the project, I need whitespaces after every element, like

dictionary = {
    'key':value,[whitespace should be here]
    'key':value,
}

The thing is, when I add those whitespaces and hit crtl-s, they disappear. I was looking through the settings, searching by "spaces" keyword, but I've found only highlighting option, nothing that would change or delete them for me.

Any ideas what this might be?

Thanks
Greg