For a given document (buffer), I would like use left double quotation mark `“` (U+201C) and right double quotation mark `”` (U+201D) instead of the ordinary double quote `"` (U+0022). I want to surround strings and sentences with these, and I want to do it as effortless as possible.

I post my first attempt as an answer below, since it works somehow..

Is this a recommended approach? I am looking for feedback and alternatives.