}
								}
								calculated := calculated[off:]
								inFile := sh[off:]
								extra := ""
								if len(calculated) != len(inFile) {
									fmt.Println("SIZE MISMATCH", len(calculated), len(inFile))
								} else if len(calculated) > 10 {
									calculated = calculated[:10]
									inFile = inFile[:10]
									extra = "..."
								}

	"fmt"
	"slices"

	"github.com/tinylib/msgp/msgp"
)

// xlMetaInlineData is serialized data in [string][]byte pairs.
type xlMetaInlineData []byte

// xlMetaInlineDataVer indicates the version of the inline data structure.
const xlMetaInlineDataVer = 1

// versionOK returns whether the version is ok.
func (x xlMetaInlineData) versionOK() bool {
	if len(x) == 0 {
		return true
	}

You can use `async def` or normal `def`.

And you can declare dependencies with `async def` inside of normal `def` *path operation functions*, or `def` dependencies inside of `async def` *path operation functions*, etc.

It doesn't matter. **FastAPI** will know what to do.

/// note

```

### More technical details { #more-technical-details }

You might have noticed that `await` can only be used inside of functions defined with `async def`.

But at the same time, functions defined with `async def` have to be "awaited". So, functions with `async def` can only be called inside of functions defined with `async def` too.

So, about the egg and the chicken, how do you call the first `async` function?

///

## Create a Project { #create-a-project }

First, create a directory for your project.

What I normally do is that I create a directory named `code` inside my home/user directory.

And inside of that I create one directory per project.

<div class="termy">

```console
// Go to the home directory
$ cd
// Create a directory for all your code projects
$ mkdir code

        assertEquals("BoostQuery", boostQueryCommand.getQueryClassName());
    }

    public void test_execute_withTermQuery() {
        // Test executing BoostQuery with a TermQuery inside
        Term term = new Term("field", "value");
        TermQuery termQuery = new TermQuery(term);
        BoostQuery boostQuery = new BoostQuery(termQuery, 2.5f);

	// if object upload fails stop the test.
	if err != nil {
		t.Fatalf("Error uploading object: <ERROR> %v", err)
	}

	// initialize httptest Recorder, this records any mutations to response writer inside the handler.
	rec := httptest.NewRecorder()
	// construct HTTP request for DELETE bucket.

	for i, testCase := range testCases {
		// obtain the put bucket policy request body.
		// initialize HTTP NewRecorder, this records any mutations to response writer inside the handler.
		recV4 := httptest.NewRecorder()
		// construct HTTP request for PUT bucket policy endpoint.
		reqV4, err := newTestSignedRequestV4(http.MethodPut, getPutPolicyURL("", testCase.bucketName),

The `TestClient` does some magic inside to call the asynchronous FastAPI application in your normal `def` test functions, using standard pytest. But that magic doesn't work anymore when we're using it inside asynchronous functions. By running our tests asynchronously, we can no longer use the `TestClient` inside our test functions.

{* ../../docs_src/query_params_str_validations/tutorial002_an_py310.py hl[9] *}

Notice that the default value is still `None`, so the parameter is still optional.