# Background Tasks { #background-tasks }

You can define background tasks to be run *after* returning a response.

This is useful for operations that need to happen after a request, but that the client doesn't really have to be waiting for the operation to complete before receiving the response.

This includes, for example:

* Email notifications sent after performing an action:

	} unicode_string;

	/* 
	 * typedef struct _SID_IDENTIFIER_AUTHORITY {
	 *     UCHAR Value[6];
	 * } SID_IDENTIFIER_AUTHORITY, *PSID_IDENTIFIER_AUTHORITY;
	 * 
	 * #define SECURITY_NT_AUTHORITY           {0,0,0,0,0,5}
	 * 
	 * typedef struct _SID {
	 *    UCHAR Revision;
	 *    UCHAR SubAuthorityCount;
	 *    SID_IDENTIFIER_AUTHORITY IdentifierAuthority;

	} unicode_string;

	/* 
	 * typedef struct _SID_IDENTIFIER_AUTHORITY {
	 *     UCHAR Value[6];
	 * } SID_IDENTIFIER_AUTHORITY, *PSID_IDENTIFIER_AUTHORITY;
	 * 
	 * #define SECURITY_NT_AUTHORITY           {0,0,0,0,0,5}
	 * 
	 * typedef struct _SID {
	 *    UCHAR Revision;
	 *    UCHAR SubAuthorityCount;
	 *    SID_IDENTIFIER_AUTHORITY IdentifierAuthority;

// errVolumeAccessDenied - cannot access volume, insufficient permissions.
var errVolumeAccessDenied = StorageErr("volume access denied")

// errFileAccessDenied - cannot access file, insufficient permissions.
var errFileAccessDenied = StorageErr("file access denied")

// errFileCorrupt - file has an unexpected size, or is not readable
var errFileCorrupt = StorageErr("file is corrupted")

			Description: `sleep between each retries, allowed maximum value is '1m' e.g. '10s'`,
			Optional:    true,
			Type:        "duration",
		},
		config.HelpKV{
			Key:         httpTimeout,
			Description: `defines the maximum duration for each http request`,
			Optional:    true,
			Type:        "duration",
		},
		config.HelpKV{
			Key:         config.Comment,
			Description: config.DefaultComment,
			Optional:    true,

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

///

## Import `Form` { #import-form }

Import `Form` from `fastapi`:

{* ../../docs_src/request_forms/tutorial001_an_py39.py hl[3] *}

## Define `Form` parameters { #define-form-parameters }

Create form parameters the same way you would for `Body` or `Query`:

{* ../../docs_src/request_forms/tutorial001_an_py39.py hl[9] *}

         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <!-- Shared parent. Doesn't define a lot of things about Apache like general mailing lists, but does
       define the settings common to all projects at Apache -->
  <groupId>org.apache</groupId>
  <artifactId>apache</artifactId>
  <version>1</version>
  <packaging>pom</packaging>

        assertEquals(
                "'build.pluginManagement.plugins.plugin.(groupId:artifactId)' groupId of a plugin must be defined. ",
                result.getFatals().get(0));

        assertEquals(
                "'build.pluginManagement.plugins.plugin.(groupId:artifactId)' artifactId of a plugin must be defined. ",
                result.getFatals().get(1));
    }

    @Test

{* ../../docs_src/using_request_directly/tutorial001_py39.py hl[1,7:8] *}

Durch die Deklaration eines *Pfadoperation-Funktionsparameters*, dessen Typ der `Request` ist, weiß **FastAPI**, dass es den `Request` diesem Parameter übergeben soll.

/// tip | Tipp

Beachten Sie, dass wir in diesem Fall einen Pfad-Parameter zusätzlich zum Request-Parameter deklarieren.

        }
    }

    @Nested
    @DisplayName("Interface Method Contract Tests")
    class InterfaceMethodContractTests {

        @Test
        @DisplayName("Should define getSID method returning SID")
        void shouldDefineMethods() {
            ACE ace = mock(ACE.class);
            SID mockSid = mock(SID.class);
            when(ace.getSID()).thenReturn(mockSid);