{* ../../docs_src/background_tasks/tutorial001_py39.py hl[14] *}

`.add_task()` receives as arguments:

* A task function to be run in the background (`write_notification`).
* Any sequence of arguments that should be passed to the task function in order (`email`).

///

## Other Asynchronous Function Calls { #other-asynchronous-function-calls }

As the testing function is now asynchronous, you can now also call (and `await`) other `async` functions apart from sending requests to your FastAPI application in your tests, exactly as you would call them anywhere else in your code.

/// tip

Maybe you need to start a new version, or you just got tired of running it. 🤷

///

### Lifespan function { #lifespan-function }

The first thing to notice, is that we are defining an async function with `yield`. This is very similar to Dependencies with `yield`.

{* ../../docs_src/events/tutorial003_py39.py hl[14:19] *}

The first part of the function, before the `yield`, will be executed **before** the application starts.

    rect rgba(0, 255, 0, .1)
        code ->> function: say_hi(name="Camila")
        function ->> execute: führe Code der Funktion aus
        execute ->> code: gib das Resultat zurück
    end

    rect rgba(0, 255, 255, .1)
        code ->> function: say_hi(name="Camila")
        function ->> code: gib das gespeicherte Resultat zurück
    end

    rect rgba(0, 255, 0, .1)

  Define(1, {add}, {feed1, feed2}, {add, scalar}, {}, true);
  EXPECT_EQ(TF_INVALID_ARGUMENT, TF_GetCode(s_));
  EXPECT_EQ(string("TF_Output scalar:0 is neither in the function body nor "
                   "among function inputs. Encountered while creating "
                   "function 'MyFunc'"),
            string(TF_Message(s_)));
}

void DefineFunction(const char* name, TF_Function** func,

Then, the arguments of the call are <i>passed</i> to the function,
which means that they are <a href="#Assignment_statements">assigned</a>
to their corresponding function parameters,
and the called function begins execution.
The return parameters of the function are passed
back to the caller when the function returns.
</p>

<p>
Calling a <code>nil</code> function value
causes a <a href="#Run_time_panics">run-time panic</a>.

    return value


client = TestClient(app)


@pytest.mark.parametrize(
    "route,value",
    [
        ("/partial-function-dependency", "partial-function-dependency"),
        (
            "/partial-async-function-dependency",
            "partial-async-function-dependency",
        ),
        ("/partial-gen-dependency", "partial-gen-dependency"),

   * {@link java.util.stream.Collectors#toMap(java.util.function.Function,
   * java.util.function.Function) Collectors.toMap(Function, Function)}, which throws an {@code
   * IllegalStateException}.)
   *
   * @since 21.0
   */
  public static <T extends @Nullable Object, K extends Enum<K>, V>
      Collector<T, ?, ImmutableMap<K, V>> toImmutableEnumMap(
          java.util.function.Function<? super T, ? extends K> keyFunction,

</p>

<p>
Each function also needs annotations giving the location of
live pointers in its arguments, results, and local stack frame.
For an assembly function with no pointer results and
either no local stack frame or no function calls,
the only requirement is to define a Go prototype for the function
in a Go source file in the same package. The name of the assembly

participant code as Code
participant function as say_hi()
participant execute as Execute function

    rect rgba(0, 255, 0, .1)
        code ->> function: say_hi(name="Camila")
        function ->> execute: execute function code
        execute ->> code: return the result
    end

    rect rgba(0, 255, 255, .1)
        code ->> function: say_hi(name="Camila")
        function ->> code: return stored result
    end