In fact, in some cases, it will even have **two JSON Schemas** in OpenAPI for the same Pydantic model, for input and output, depending on if they have **default values**.

Let's see how that works and how to change it if you need to do that.

## Pydantic Models for Input and Output { #pydantic-models-for-input-and-output }

Let's say you have a Pydantic model with default values, like this one:

                "tearDownTwo should have been run before tearDownOne", false, tearDownOne.ran);
          }
        };

    SimpleTearDown tearDownTwo = new SimpleTearDown(callback);
    stack.addTearDown(tearDownTwo);

    assertEquals(false, tearDownOne.ran);
    assertEquals(false, tearDownTwo.ran);

    stack.runTearDown();

    assertEquals("tearDownOne should have run", true, tearDownOne.ran);

from your submission, but they are here to help bring them to your
attention.
-->

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- If submitting code, have you built your formula locally prior to submission with `gradle check`?

But `OAuth2PasswordRequestForm` is just a class dependency that you could have written yourself, or you could have declared `Form` parameters directly.

But as it's a common use case, it is provided by **FastAPI** directly, just to make it easier.

///

### Use the form data { #use-the-form-data }

/// tip

        // When - Get a buffer
        byte[] buffer = BufferCache.getBuffer();

        // Then - Buffer should have expected size
        assertNotNull(buffer, "Buffer should not be null");
        assertEquals(SmbComTransaction.TRANSACTION_BUF_SIZE, buffer.length, "Buffer should have TRANSACTION_BUF_SIZE");

        // The validation in getBuffer() ensures size is within bounds (0 < size <= 1MB)

        // Create next index
        suggester.createNextIndex();

        // Verify we now have two indices
        GetIndexResponse response = runner.admin().indices().prepareGetIndex().addIndices(getIndexName() + "*").execute().actionGet();
        assertEquals("Should have two indices", 2, response.getIndices().length);
    }

    @Test
    public void test_switchIndex_works() throws Exception {

            }
        };

        // When/Then
        assertTrue(iterator.hasNext(), "Should have first element");
        SmbResource first = iterator.next();
        assertNotNull(first, "First element should not be null");
        assertEquals("file1.txt", first.getName());

        assertTrue(iterator.hasNext(), "Should have second element");
        SmbResource second = iterator.next();

	if sepIndex == -1 {
		return nil, fmt.Errorf("'%s' does not have a valid range value", rangeString)
	}

	offsetBeginString := byteRangeString[:sepIndex]
	offsetBegin := int64(-1)
	// Convert offsetBeginString only if its not empty.
	if len(offsetBeginString) > 0 {
		if offsetBeginString[0] == '+' {
			return nil, fmt.Errorf("Byte position ('%s') must not have a sign", offsetBeginString)

    * A special case is `204`, "No Content".  This response is used when there is no content to return to the client, and so the response must not have a body.
* **`300 - 399`** are for "Redirection".  Responses with these status codes may or may not have a body, except for `304`, "Not Modified", which must not have one.
* **`400 - 499`** are for "Client error" responses. These are the second type you would probably use the most.

Do you want to have an `id` and `email` and not have any `username` in your model? Sure. You can use these same tools.

Do you want to just have a `str`? Or just a `dict`? Or a database class model instance directly? It all works the same way.

You actually don't have users that log in to your application but robots, bots, or other systems, that have just an access token? Again, it all works the same.