[Python] How to define query parameters using Pydantic model in FastAPI?

I am trying to have an endpoint like /services?status=New

status is going to be either New or Old

Here is my code:

from fastapi import APIRouter, Depends
from pydantic import BaseModel
from enum import Enum

router = APIRouter()

class ServiceStatusEnum(str, Enum):
new = "New"
old = "Old"


class ServiceStatusQueryParam(BaseModel):
status: ServiceStatusEnum


@router.get("/services")
def get_services(
status: ServiceStatusQueryParam = Query(..., title="Services", description="my desc"),
):
pass #my code for handling this route.....


The result is that I get an error that seems to be relevant to this issue here

The error says AssertionError: Param: status can only be a request body, using Body()


Then I found another solution explained here.

So, my code will be like this:

from fastapi import APIRouter, Depends
from pydantic import BaseModel
from enum import Enum

router = APIRouter()

class ServiceStatusEnum(str, Enum):
new = "New"
old = "Old"


class ServicesQueryParam(BaseModel):
status: ServiceStatusEnum


@router.get("/services")
def get_services(
q: ServicesQueryParam = Depends(),
):
pass #my code for handling this route.....


It is working (and I don't understand why) - but the question is how and where do I add the description and title?

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