case 1:
                return 1;
              case 2:
                return endOfData();
              default:
                throw new AssertionError("Should not have been invoked again");
            }
          }
        };

    assertTrue(iter.hasNext());
    assertEquals(0, (int) iter.next());

    // verify idempotence of hasNext()
    assertTrue(iter.hasNext());

              case 1:
                return 1;
              case 2:
                return endOfData();
              default:
                throw new AssertionError("Should not have been invoked again");
            }
          }
        };

    assertTrue(iter.hasNext());
    assertEquals(0, (int) iter.next());

    // verify idempotence of hasNext()
    assertTrue(iter.hasNext());

#### `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.

              case 1:
                return 1;
              case 2:
                return endOfData();
              default:
                throw new AssertionError("Should not have been invoked again");
            }
          }
        };

    assertTrue(iter.hasNext());
    assertEquals(0, (int) iter.next());

    // verify idempotence of hasNext()
    assertTrue(iter.hasNext());

              case 1:
                return 1;
              case 2:
                return endOfData();
              default:
                throw new AssertionError("Should not have been invoked again");
            }
          }
        };

    assertTrue(iter.hasNext());
    assertEquals(0, (int) iter.next());

    // verify idempotence of hasNext()
    assertTrue(iter.hasNext());

                rate_limit: 'It\'s currently busy. Please wait a moment and try again.',
                auth_error: 'AI service authentication failed. Please contact the administrator.',
                service_unavailable: 'The AI service is temporarily unavailable. Please try again later.',
                timeout: 'The request timed out. Please try again.',

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

errors.app.illegal.transition = Illegal transition. Please try again.
errors.app.db.already.deleted = It may have been deleted by another process. Please try again.
errors.app.db.already.updated = It may have been updated by another process. Please try again.
errors.app.db.already.exists = The data already exists. Please try again.
errors.app.double.submit.request = It may have been processed before this request. Please try again.

errors.app.illegal.transition = Illegal transition. Please try again.
errors.app.db.already.deleted = It may have been deleted by another process. Please try again.
errors.app.db.already.updated = It may have been updated by another process. Please try again.
errors.app.db.already.exists = The data already exists. Please try again.
errors.app.double.submit.request = It may have been processed before this request. Please try again.

### 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
$ fastapi dev