from fastapi import APIRouter, HTTPException

router = APIRouter()

states_in_turkey = [
    "Adana", "Adıyaman", "Afyonkarahisar", "Ağrı", "Aksaray", "Amasya", "Ankara", "Antalya", "Ardahan", "Artvin", "Aydın", "Balıkesir", "Bartın", "Batman", "Bayburt", "Bilecik", "Bingöl", "Bitlis", "Bolu", "Burdur", "Bursa", "Çanakkale", "Çankırı", "Çorum", "Denizli", "Diyarbakır", "Düzce", "Edirne", "Elazığ", "Erzincan", "Erzurum", "Eskişehir", "Gaziantep", "Giresun", "Gümüşhane", "Hakkâri", "Hatay", "Iğdır", "Isparta", "İstanbul", "İzmir", "Kahramanmaraş", "Karabük", "Karaman", "Kars", "Kastamonu", "Kayseri", "Kilis", "Kırıkkale", "Kırklareli", "Kırşehir", "Kocaeli", "Konya", "Kütahya", "Malatya", "Manisa", "Mardin", "Mersin", "Muğla", "Muş", "Nevşehir", "Niğde", "Ordu", "Osmaniye", "Rize", "Sakarya", "Samsun", "Şanlıurfa", "Siirt", "Sinop", "Sivas", "Şırnak", "Tekirdağ", "Tokat", "Trabzon", "Tunceli", "Uşak", "Van", "Yalova", "Yozgat", "Zonguldak"
]

@router.post("/turkey")
async def get_states_in_turkey():
    """Returns list of states in Turkey"""
    if request.method != "POST":
        raise HTTPException(status_code=405, detail="Method Not Allowed")

    return {
        "method": "POST",
        "_verb": "post",
        "states": states_in_turkey
    }
```

This code defines a FastAPI endpoint `/turkey` that returns a list of states in Turkey when a POST request is made to that endpoint. It follows the provided guidelines for method adherence, response format, and error handling.