$ python -u "/Users/yhx2010/Desktop/main.py"
INFO:     Will watch for changes in these directories: ['/Users/yhx2010']
INFO:     Uvicorn running on http://0.0.0.0:8000 (Press CTRL+C to quit)
INFO:     Started reloader process [87876] using StatReload
INFO:     Started server process [87881]
INFO:     Waiting for application startup.
INFO:     Application startup complete.
Traceback (most recent ca...