Real-life example

_I cannot believe I have missed this project while extensively using `apispec`, `marshamallow`, `marshmallow-sqlalchemy`, `flask-marshmallow`, and `webargs` (almost every other project related to marshmallow!)._

I have been writing several personal RESTful API servers and, as a result, decided to share a somewhat ["real-life" RESTful API server example](https://github.com/frol/flask-restplus-server-example). I had to patch Flask-RESTplus to add `marshmallow`/`webargs` support (via `apispec`), but I would probably start with `flask-apispec` if I had known about it.

I consider my example as a reasonably well-written, so you might get some ideas from it. BTW, you may also share the parts you find weird in my example.

Cheers!

No repository file, test, or concrete change is named. Start by reviewing the linked flask-restplus-server-example and the flask-apispec documentation to determine whether an example should be added or adapted; done requires a clearly agreed example scope and acceptance criteria.

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