error deploying a tsx with deno deploy

HELP

I want to deploy a deno tsx (also using python) with dash.deno.com and recieved this message:

Failed to deploy:

UNCAUGHT_EXCEPTION

Error: Cannot load dynamic library because --unstable flag was not set
at https://deno.land/x/python@0.4.3/src/ffi.ts:46:13

This is the jsonc:

{
"tasks": {
"start": "deno run --allow-net=:8000 --unstable --allow-ffi --allow-env server.tsx"
}
}

So --unstable is set !

I don't understand the error.

Thank's for helping :)

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