#### `lru_cache` Technical Details { #lru-cache-technical-details }

`@lru_cache` modifies the function it decorates to return the same value that was returned the first time, instead of computing it again, executing the code of the function every time.

### Delete a Hero Again { #delete-a-hero-again }

**Deleting** a hero stays pretty much the same.

We won't satisfy the desire to refactor everything in this one. 😅

{* ../../docs_src/sql_databases/tutorial002_an_py310.py ln[96:103] hl[101] *}

### Run the App Again { #run-the-app-again }

You can run the app again:

<div class="termy">

```console

app = FastAPI()


class InternalError(Exception):
    pass


def get_username():
    try:
        yield "Rick"
    except InternalError:
        print("Oops, we didn't raise again, Britney 😱")


@app.get("/items/{item_id}")
def get_item(item_id: str, username: str = Depends(get_username)):
    if item_id == "portal-gun":
        raise InternalError(

FROM $BASE_IMAGE AS devel
# See https://docs.docker.com/reference/dockerfile/#understand-how-arg-and-from-interact
# on why we cannot reference BASE_IMAGE again unless we declare it again.
################################################################################

# Install devtoolset build dependencies
COPY setup.sources.sh /setup.sources.sh
COPY setup.packages.sh /setup.packages.sh

app = FastAPI()


class InternalError(Exception):
    pass


def get_username():
    try:
        yield "Rick"
    except InternalError:
        print("We don't swallow the internal error here, we raise again 😎")
        raise


@app.get("/items/{item_id}")
def get_item(item_id: str, username: str = Depends(get_username)):
    if item_id == "portal-gun":
        raise InternalError(

          for i in 1 2 3 4 5; do
            if smokeshow upload htmlcov; then
                echo "Smokeshow upload success!"
                break
            fi
            echo "Smokeshow upload error, sleep 1 sec and try again."
            sleep 1
          done
        env:
          SMOKESHOW_GITHUB_STATUS_DESCRIPTION: Coverage {coverage-percentage}
          SMOKESHOW_GITHUB_COVERAGE_THRESHOLD: 100

For example, imagine you have code that uses a database session in a dependency with `yield` only to verify a user, but the database session is never used again in the *path operation function*, only in the dependency, **and** the response takes a long time to be sent, like a `StreamingResponse` that sends data slowly, but for some reason doesn't use the database.

                    "summary": "Read Items",
                    "operationId": "read_items_items__get",
                }
            }
        },
    }
    openapi_schema = response.json()
    # Request again to test the custom cache
    response = client.get("/openapi.json")
    assert response.status_code == 200, response.text

This tells your GPG installation that you trust this key and will prevent the warning from appearing again.

To do this, run the following command:

```bash
gpg --sign-key 1BD97A6A154E7810EE0BC832E2F38302C8075E3D
```

## Public Key Block in ascii-armored format

```
-----BEGIN PGP PUBLIC KEY BLOCK-----

    }

    /**
     * Adds a new web protocol to the supported protocols list.
     * If the protocol already exists, it will not be added again.
     *
     * @param protocol the protocol name to add (without colon suffix)
     */
    public void addWebProtocol(final String protocol) {
        final String prefix = protocol + ":";