And `threading.local` is not compatible with the new async features of modern Python.

!!! note "Technical Details"
    `threading.local` is used to have a "magic" variable that has a different value for each thread.

```

!!! note
    Notice that you have to return the image using a `FileResponse` directly.

!!! info
    Unless you specify a different media type explicitly in your `responses` parameter, FastAPI will assume the response has the same media type as the main response class (default `application/json`).

   */
  byte[] getBytesInternal() {
    return asBytes();
  }

  /**
   * Returns whether this {@code HashCode} and that {@code HashCode} have the same value, given that
   * they have the same number of bits.
   */
  abstract boolean equalsSameBits(HashCode that);

  /**
   * Creates a 32-bit {@code HashCode} representation of the given int value. The underlying bytes

However, further setup is required to run tests or programs directly on a device.

First make sure you have a valid developer certificate and have setup your device properly
to run apps signed by your developer certificate. Then install the libimobiledevice and
ideviceinstaller tools from https://www.libimobiledevice.org/. Use the HEAD versions from
source; the stable versions have bugs that prevents the Go exec wrapper to install and run
apps.

                    // only have second precision
                    // there seems to be some random factor (adding one second)
                    int diff = Math.abs((int) ( ( time / 1000 ) - ( f.lastModified() / 1000 ) ));
                    Assert.assertTrue("Have set time correctly", diff < 2);
                }
                else {

  * In practice, this largely means that references are fully qualified in the API. IP Addresses (generally) have a network associated with them, node names have a cluster associated with them, etc.

See the [XDS Evolution](https://docs.google.com/document/d/1V5wkeBHbLSLMzAMbwFlFZNHdZPyUEspG4lHbnB0UaCg/edit) document for more history and details.

// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package cmd

import (
	"bytes"
	"fmt"
	"os"
	"strings"
	"sync"

// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package mountinfo

import (
	"fmt"
	"os"
	"path/filepath"
	"strings"

// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package lifecycle

import (
	"bytes"
	"encoding/xml"
)

# Async Tests

You have already seen how to test your **FastAPI** applications using the provided `TestClient`. Up to now, you have only seen how to write synchronous tests, without using `async` functions.