How to embed a single file from a Gist

This is a nice trick to know - see example of usage in this post:

you can embed a single file from a Gist containing multiple files by adding ?file=filename to the URL in the embed code.

Credit StackOverflow  How do I embed a single file from a GitHub gist with the new gist interface? - Stack Overflow

Example for the mentioned post, this is the first embed code for the first file:

<script src="https://gist.github.com/tdalon/254a1daa1990d22aa55b82dae7a03be3.js?file=JiraFieldName2Id.pq"></script>

Highlighted the additional file parameter.