[Python] How to initialize a global object or variable and reuse it in every FastAPI endpoint?

I am having a class to send notifications. When being initialized, it involves making a connection to a notification server, which is time-consuming. I use a background task in FastAPI to send notifications, as I don't want to delay the response due to notification. Below is the sample code.

file1.py:
noticlient = NotificationClient()

@app.post("/{data}")
def send_msg(somemsg: str, background_tasks: BackgroundTasks):
result = add_some_tasks(data, background_tasks, noticlient)
return result

file2.py:
def add_some_tasks(data, background_tasks: BackgroundTasks, noticlient):
background_tasks.add_task(noticlient.send, param1, param2)
result = some_operation
return result


Here, notification client is declared globally. I could have it initialized in file2.py under add_some_tasks, but it would get initialized every time a request arrives, and that would require some time. Is there any way to use a middleware to re-use it every time a request arrives, so that it doesn' t need to be initialized every time.

or Approach two: Initialize notification in class def

file1.py:
class childFastApi(FastAPI):
noticlient = NotificationClient()

app = childFastApi()

@app.post("/{data}")
def send_msg(somemsg: str, background_tasks: BackgroundTasks):
result = add_some_tasks(data, background_tasks, app.noticlient)
return result

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