```Python
from fastapi import FastAPI
from pydantic import BaseModel as BaseModelV2
from pydantic.v1 import BaseModel


class Item(BaseModel):
    name: str
    description: str | None = None


class ItemV2(BaseModelV2):
    title: str
    summary: str | None = None


app = FastAPI()


@app.post("/items/", response_model=ItemV2)
def create_item(item: Item):

tagMask, T *[16]byte, pLen, dLen uint64) TEXT ·gcmAesFinish(SB),NOSPLIT,$0 #define pTbl R0 #define tMsk R1 #define tPtr R2 #define plen R3 #define dlen R4 MOVD $0xC2, R1 LSL $56, R1 MOVD $1, R0 VMOV R1, POLY.D[0] VMOV R0, POLY.D[1] VEOR ZERO.B16, ZERO.B16, ZERO.B16 MOVD productTable+0(FP), pTbl MOVD tagMask+8(FP), tMsk MOVD T+16(FP), tPtr MOVD pLen+24(FP), plen MOVD dLen+32(FP), dlen VLD1 (tPtr), [ACC0.B16] VLD1 (tMsk), [B1.B16] LSL $3, plen LSL $3, dlen VMOV dlen, B0.D[0] VMOV plen, B0.D[1] ADD $14*16,...

tagMask, T *[16]byte, pLen, dLen uint64) TEXT ·gcmAesFinish(SB),NOSPLIT,$0 #define pTbl R0 #define tMsk R1 #define tPtr R2 #define plen R3 #define dlen R4 MOVD $0xC2, R1 LSL $56, R1 MOVD $1, R0 VMOV R1, POLY.D[0] VMOV R0, POLY.D[1] VEOR ZERO.B16, ZERO.B16, ZERO.B16 MOVD productTable+0(FP), pTbl MOVD tagMask+8(FP), tMsk MOVD T+16(FP), tPtr MOVD pLen+24(FP), plen MOVD dLen+32(FP), dlen VLD1 (tPtr), [ACC0.B16] VLD1 (tMsk), [B1.B16] LSL $3, plen LSL $3, dlen VMOV dlen, B0.D[0] VMOV plen, B0.D[1] ADD $14*16,...

map-get($utility, css-variable-name), map-get($utility, class));\n\n    // State params to generate pseudo-classes\n    $state: if(map-has-key($utility, state), map-get($utility, state), ());\n\n    $infix: if($property-class == \"\" and str-slice($infix, 1, 1) == \"-\", str-slice($infix, 2), $infix);\n\n    // Don't prefix if value key is null (e.g. with shadow class)\n    $property-class-modifier: if($key, if($property-class == \"\" and $infix == \"\", \"\", \"-\") + $key, \"\");\n\n    @if map-get($utility,...