## Declare model attributes { #declare-model-attributes }

You can then use `Field` with model attributes:

{* ../../docs_src/body_fields/tutorial001_an_py310.py hl[11:14] *}

`Field` works the same way as `Query`, `Path` and `Body`, it has all the same parameters, etc.

/// note | Technical Details

        ProtwordsItem item4 = new ProtwordsItem(1, "word");

        // Same object
        assertTrue(item1.equals(item1));

        // Same input, different id
        assertTrue(item1.equals(item2));

        // Different input
        assertFalse(item1.equals(item3));

        // Same id and input
        assertTrue(item1.equals(item4));

        // Null object

    for (int i = 0; i < keyBits; i++) {
      int same = 0x0; // bitset for output bits with same values
      int diff = 0x0; // bitset for output bits with different values
      int count = 0;
      // originally was 2 * Math.log(...), making it try more times to avoid flakiness issues
      int maxCount = (int) (4 * Math.log(2 * keyBits * hashBits) + 1);
      while (same != 0xffffffff || diff != 0xffffffff) {

As they are part of the URL, they are "naturally" strings.

But when you declare them with Python types (in the example above, as `int`), they are converted to that type and validated against it.

All the same process that applied for path parameters also applies for query parameters:

* Editor support (obviously)
* Data <dfn title="converting the string that comes from an HTTP request into Python data">"parsing"</dfn>
* Data validation

# Request Forms and Files { #request-forms-and-files }

You can define files and form fields at the same time using `File` and `Form`.

/// info

To receive uploaded files and/or form data, first install [`python-multipart`](https://github.com/Kludex/python-multipart).

Make sure you create a [virtual environment](../virtual-environments.md), activate it, and then install it, for example:

```console
$ pip install python-multipart
```

///

    }

    @Test
    @DisplayName("getConfig should return the provided configuration")
    void testGetConfig() {
        // When
        Configuration config = context.getConfig();

        // Then
        assertSame(mockConfig, config, "Should return the same configuration instance");
    }

    @Test

        StopwordsItem item2 = new StopwordsItem(1, "test");
        StopwordsItem item3 = new StopwordsItem(2, "test");
        StopwordsItem item4 = new StopwordsItem(1, "different");

        // Same input should have same hashCode regardless of id
        assertEquals(item1.hashCode(), item2.hashCode());
        assertEquals(item1.hashCode(), item3.hashCode());

        // Different input should have different hashCode

        // Second call should return cached value (same as first)
        Subject second = auth.getSubject();
        if (first == null && second == null) {
            // Both null - caching is working
            assertNull(second, "Second getSubject should return same result as first (both null)");
        } else if (first != null && second != null) {
            // Both non-null - should be same instance

    }
}
```

/// note

Notice that even though the `item` was declared the same way as before, it is now expected to be inside of the body with a key `item`.

///

**FastAPI** will do the automatic conversion from the request, so that the parameter `item` receives its specific content and the same for `user`.

    * So, by using FastAPI you are saving development time, bugs, lines of code, and you would probably get the same performance (or better) you would if you didn't use it (as you would have to implement it all in your code).