Visual Studio keyboard shortcut to collapse and expand code

Sometimes in Visual Studio you need to collapse all code to give your mind a quick clean and refresh, at least I feel it helps.

The Visual Studio keyboard shortcut to do this is as follows:

Ctrl + M + O for collapse

Ctrl + M + L for expand.

StackOverflow has a very popular question and answer with the shortcuts which leads me to believe that I cannot be alone in my need to occasionally collapse all to preserve my sanity.