list *LruList[K, V]

	// The LRU Key of this element.
	Key K

	// The Value stored with this element.
	Value V

	// The time this element would be cleaned up, optional
	ExpiresAt time.Time

	// The expiry bucket item was put in, optional
	ExpireBucket uint8
}

// PrevEntry returns the previous list element or nil.
func (e *Entry[K, V]) PrevEntry() *Entry[K, V] {

            cb.paging(userPager.getPageSize(), userPager.getCurrentPageNumber());
            setupListCondition(cb, userPager);
        });

        // update pager
        BeanUtil.copyBeanToBean(userList, userPager, option -> option.include(Constants.PAGER_CONVERSION_RULE));
        userPager.setPageNumberList(userList.pageRange(op -> {
            op.rangeSize(fessConfig.getPagingPageRangeSizeAsInteger());
        }).createPageNumberList());

        assertThrows(jcifs.CIFSException.class, () -> transport.getDfsReferrals(ctx, nullName, "h", "d", 1));
        verify(transport).getDfsReferrals(eq(ctx), isNull(), eq("h"), eq("d"), eq(1));
    }

    // Signing modes: optional vs enforced
    @Test
    @DisplayName("isSigningOptional and isSigningEnforced reflect configuration")
    void signingModes() throws Exception {
        when(transport.isSigningOptional()).thenReturn(true);

Das ist keine Limitation von **FastAPI**, sondern Teil des HTTP-Protokolls.

///

## Optionaler Datei-Upload

Sie können eine Datei optional machen, indem Sie Standard-Typannotationen verwenden und den Defaultwert auf `None` setzen:

{* ../../docs_src/request_files/tutorial001_02_an_py310.py hl[9,17] *}

import org.dbflute.cbean.ConditionBean;
import org.dbflute.cbean.result.ListResultBean;
import org.dbflute.cbean.result.PagingResultBean;
import org.dbflute.exception.IllegalBehaviorStateException;
import org.dbflute.optional.OptionalEntity;
import org.dbflute.util.DfTypeUtil;
import org.opensearch.action.bulk.BulkRequestBuilder;
import org.opensearch.action.delete.DeleteRequestBuilder;
import org.opensearch.action.index.IndexRequestBuilder;

import org.dbflute.cbean.ConditionBean;
import org.dbflute.cbean.result.ListResultBean;
import org.dbflute.cbean.result.PagingResultBean;
import org.dbflute.exception.IllegalBehaviorStateException;
import org.dbflute.optional.OptionalEntity;
import org.dbflute.util.DfTypeUtil;
import org.opensearch.action.bulk.BulkRequestBuilder;
import org.opensearch.action.delete.DeleteRequestBuilder;
import org.opensearch.action.index.IndexRequestBuilder;

import jakarta.servlet.http.HttpServletRequest;

import org.codelibs.fess.mylasta.direction.FessConfig;
import org.codelibs.fess.unit.UnitFessTestCase;
import org.codelibs.fess.util.ComponentUtil;
import org.dbflute.optional.OptionalThing;
import org.lastaflute.web.path.ActionPathResolver;
import org.lastaflute.web.ruts.process.ActionRuntime;
import org.lastaflute.web.servlet.request.RequestManager;

//           # retainVersions: 0 # (default) delete all versions of the object. This option is the fastest.
//           # retainVersions: 5 # keep the latest 5 versions of the object including delete markers.
//
//   notify:
//     endpoint: https://notify.endpoint # notification endpoint to receive job completion status
//     token: Bearer xxxxx # optional authentication token for the notification endpoint
//
//   retry:

 * to add or remove multiple occurrences of an element at once, or to set the count of an element to
 * a specific value. These modification operations are optional, but implementations which support
 * the standard collection operations {@link #add(Object)} or {@link #remove(Object)} are encouraged
 * to implement the related methods as well. Finally, two collection views are provided: {@link

```Python hl_lines="9  14"
from typing import Optional

from fastapi import FastAPI

app = FastAPI()


@app.get("/")
async def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
async def read_item(item_id: int, q: Optional[str] = None):
    return {"item_id": item_id, "q": q}
```

**توجه**: