pydantic

First check

• I added a very descriptive title to this issue.
• I used the GitHub search to find a similar issue and didn't find it.
• I searched the FastAPI documentation, with the integrated search.
• I already searched in Google "How to X in FastAPI" and didn't find any information.
• I already read and followed all the tutorial in the docs and didn't find an answ

add documents include examples on each feature.

There two official example projects:

• FastAPI Demo - Beanie and FastAPI collaboration demonstration. CRUD and Aggregation.
• Indexes Demo - Regular and Geo Indexes usage example wrapped to a microservice.

Both should:

• Show, how to use current Beanie syntax
• Contain unit tests