///

```Python hl_lines="8  13"
{!> ../../docs_src/dependencies/tutorial006.py!}
```

////

### Return values

And they can return values or not, the values won't be used.

So, you can reuse a normal dependency (that returns a value) you already use somewhere else, and even though the value won't be used, the dependency will be executed:

//// tab | Python 3.9+

```Python hl_lines="11  16"

		close(r.decoded)
		readCloser.Close()
		for range r.input {
			// Read until EOF trickles through.
			// Otherwise, we risk the decoder hanging.
		}
		r.readerWg.Done()
	}

	// We cannot reuse as we are sending parsed objects elsewhere.
	simdjson.ParseNDStream(readCloser, r.input, nil)
	r.readerWg.Add(1)
	go r.startReader()
	return &r
}

// NewElementReader - creates new JSON reader using readCloser.

      total += buf.remaining();
      Java8Compatibility.clear(buf);
    }
    return total;
  }

  // TODO(lukes): consider allowing callers to pass in a buffer to use, some callers would be able
  // to reuse buffers, others would be able to size them more appropriately than the constant
  // defaults

  /**
   * Copies all characters between the {@link Reader} and {@link StringBuilder} objects. Does not

    /**
     * Gets the model cache to use for reuse of previously built models.
     *
     * @return The model cache or {@code null} if not set.
     */
    ModelCache getModelCache();

    /**
     * Sets the model cache to use for reuse of previously built models. This is an optional component that serves
     * performance optimizations.
     *

		} else {
			if o.pool < len(z.serverPools) && o.set < len(z.serverPools[o.pool].sets) {
				o.debugln("Resuming", o)
				entries, err = z.serverPools[o.pool].sets[o.set].streamMetadataParts(ctx, *o)
				entries.reuse = true // We read from stream and are not sharing results.
				if err == nil {
					return entries, nil
				}
			} else {
				err = fmt.Errorf("invalid pool/set")
				o.pool, o.set = 0, 0
			}
		}

**FastAPI** knows what to do in each case and how to reuse the same object, so that all the background tasks are merged together and are run in the background afterwards:


{* ../../docs_src/background_tasks/tutorial002_an_py310.py hl[13,15,22,25] *}

        return new LinkMetaData(methodMetaData.style, displayName, urlFragment);
    }

    private MethodLinkMetaData findMethod(String method) {
        if (method.endsWith("...)")) {
            // Should reuse the link parsing stuff from JavadocLinkConverter instead
            method = method.substring(0, method.length() - 4) + "[])";
        }

        MethodLinkMetaData metaData = methods.get(method);

	shardSize  int64
	hashBytes  []byte
}

func (b *streamingBitrotReader) Close() error {
	if b.rc == nil {
		return nil
	}
	if closer, ok := b.rc.(io.Closer); ok {
		// drain the body for connection reuse at network layer.
		xhttp.DrainBody(io.NopCloser(b.rc))
		return closer.Close()
	}
	return nil
}

func (b *streamingBitrotReader) ReadAt(buf []byte, offset int64) (int, error) {
	var err error

      } catch (e: IOException) {
        carrier.noNewExchanges()
        responseBodyComplete()
        throw e
      }
    }

    /**
     * Closes the cache entry and makes the socket available for reuse. This should be invoked when
     * the end of the body has been reached.
     */
    fun responseBodyComplete() {
      if (state == STATE_CLOSED) return

    // Check that a fresh connection was created, either immediately or after attempting reuse.
    // We know that a fresh connection was created if the server recorded a request with sequence
    // number 0. Since the client may have attempted to reuse the broken connection just before
    // creating a fresh connection, the server may have recorded 2 requests at this point. The order