Npm run vercel:dev failed due to python config?

here is my config

1{2  "version": 2,3  "devCommand": "npm run dev",4  "functions": {5    "api/index.py": {6      "runtime": "vercel-python@3.9"7    }8  },9  "routes": [10    {11      "src": "/api/(.*)",12      "dest": "/api/index.py"13    },14    {15      "src": "/(.*)",16      "dest": "/index.html"17    }18  ]19}20

expect successfully run

1npm run vercel:dev234> vue-project@0.0.0 vercel:dev5> vercel dev67Vercel CLI 44.2.78Error: Function Runtimes must have a valid version, for example `now-php@1.0.0`.

source code: https://github.com/dotku/tso-vue-project/tree/bug-vercel-config