Without a data validation system, you would have to do all the checks by hand, in code.

These features are what Marshmallow was built to provide. It is a great library, and I have used it a lot before.

As part of that, I needed to investigate, test and use many alternatives.

The history of **FastAPI** is in great part the history of its predecessors.

As said in the section [Alternatives](alternatives.md){.internal-link target=_blank}:

<blockquote markdown="1">

**FastAPI** wouldn't exist if not for the previous work of others.

dear!  I'd nearly forgotten that I've got to grow up again!  Let
me see--how IS it to be managed?  I suppose I ought to eat or
drink something or other; but the great question is, what?'

  The great question certainly was, what?  Alice looked all round
her at the flowers and the blades of grass, but she did not see
anything that looked like the right thing to eat or drink under

async def update_item(item_id: str):
    if item_id != "plumbus":
        raise HTTPException(
            status_code=403, detail="You can only update the item: plumbus"
        )

dear!  I'd nearly forgotten that I've got to grow up again!  Let
me see--how IS it to be managed?  I suppose I ought to eat or
drink something or other; but the great question is, what?'

  The great question certainly was, what?  Alice looked all round
her at the flowers and the blades of grass, but she did not see
anything that looked like the right thing to eat or drink under

async def update_item(item_id: str):
    if item_id != "plumbus":
        raise HTTPException(
            status_code=403, detail="You can only update the item: plumbus"
        )

async def update_item(item_id: str):
    if item_id != "plumbus":
        raise HTTPException(
            status_code=403, detail="You can only update the item: plumbus"
        )

# External Links and Articles

**FastAPI** has a great community constantly growing.

There are many posts, articles, tools, and projects, related to **FastAPI**.

Here's an incomplete list of some of them.

!!! tip

=================

Thank you so much for wanting to contribute to Guava! Here are a few important
things you should know about contributing:

1.  API changes require discussion, use cases, etc. Code comes later.
2.  Pull requests are great for small fixes for bugs, documentation, etc.
3.  Pull requests are not merged directly into the master branch.
4.  Code contributions require signing a Google CLA.

API changes
-----------

- To run `make test` and `make build` completes.

### Commit changes

After verification, commit your changes. This is a [great post](https://chris.beams.io/posts/git-commit/) on how to write useful commit messages

```
git commit -am 'Add some feature'
```

### Push to the branch