Keyboard Interrupt Error When Running Dev Instance of Uvicorn

[pollyandhiscat]

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Example Code

from typing import Union

from fastapi import FastAPI

app = FastAPI()

@app.get("/")
def read_root():
    return {"Greetings": "Earthling"}

Description

When you have Uvicorn running in dev mode with FastAPI and save the 'main.py' file while the program is running, a quite monstrous error appears in the terminal, which ultimately amounts to a keyboard interrupt error. The following screenshots illustrate the issue:

Operating System

Windows

Operating System Details

Windows 11 Pro

FastAPI Version

0.111.0

Pydantic Version

2.7.0

Python Version

3.12.2

Additional Context

No response

[YuriiMotov]

Where were some problems in Uvicorn that caused such errors.
I believe it's been fixed.