Skipping a region when reformatting source code

I want to skip a region when reformatting source code. When I found this page of the documentation I thought I found the solution, but either there is a problem on the documentation or I need help understanding it.

The documentation says create a line comment (Ctrl+Slash) and shows and example with //@formatter:off. 

I think there is a problem because the comments in Python start with #, not with //, and because I tried and failed with all these options:

#@formatter:off

//@formatter:off

#//@formatter:off

I am using PyCharm Pro 2017.3.3