Scaffolding other types of files: What filename should I put in?

In the `Scaffolding other types of files`, you provided an T4 example, but not mentioned about the filename and where should I put it into. I don't know how to use this Mermaid T4 script.

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* ID: cae415b7-c0ea-4d96-9d17-7e7d3163c09d
* Version Independent ID: cae415b7-c0ea-4d96-9d17-7e7d3163c09d
* Content: [Custom Reverse Engineering Templates - EF Core](https://learn.microsoft.com/en-us/ef/core/managing-schemas/scaffolding/templates?WT.mc_id=DT-MVP-4015686&tabs=dotnet-core-cli)
* Content Source: [entity-framework/core/managing-schemas/scaffolding/templates.md](https://github.com/dotnet/EntityFramework.Docs/blob/main/entity-framework/core/managing-schemas/scaffolding/templates.md)
* Product: **entity-framework**
* Technology: **entity-framework-core**
* GitHub Login: @bricelam
* Microsoft Alias: **avickers**