Templating: the first attempt at an answer
Back in the first post, I posed a question to myself:
There's something called templating. My IDE (PyCharm) seems to support this. No idea what it's for. Perhaps it'll be important.
After having a play with templating, it appears that it's used for creating a template for a webpage that allows variables to be substituted into it. Additionally, it also seems to allow some logic to decide what statements should be added to a web page (i.e. different lines can be added to a page based on the value of a variable).
I'm sure templating allows much more, but that's a start.