In Ruby we can create module functions for named methods that may be called with the module as a receiver, and these functions also become available as instance methods to classes that mix in the module. There are multiple techniques to achieve this in Ruby, but the simplest and best known are Module#module_function and extend self.
Ruby supports magic comments (interpreter instructions) at the top of the source file, mostly known for setting a source files' Encoding. But there is more you can do.
This is one hard to find out there so here it is. How to remove an updated file from a pull request whose content is changed but is out of the scope for this pull request. Now you want to remove the file from the pull request without deleting the file itself, not delete the file itself, but just revert the inclusion of this file in the pull request because, if you delete the file, then that deletion becomes part of your changeset, which is not what you wanted at all.