Even if your **FastAPI** application uses normal `def` functions instead of `async def`, it is still an `async` application underneath.

The `TestClient` does some magic inside to call the asynchronous FastAPI application in your normal `def` test functions, using standard pytest. But that magic doesn't work anymore when we're using it inside asynchronous functions. By running our tests asynchronously, we can no longer use the `TestClient` inside our test functions.

    private static final String S2C_SEAL_CONSTANT = "session key to server-to-client sealing key magic constant";

    private static final String C2S_SIGN_CONSTANT = "session key to client-to-server signing key magic constant";
    private static final String C2S_SEAL_CONSTANT = "session key to client-to-server sealing key magic constant";

/// tip

The important and "magic" thing here is that `get_current_user` will have a different list of `scopes` to check for each *path operation*.

        }

        for (;;) {
            /*
             * 01234567
             * 00SSFSMB
             * 0 - 0's
             * S - size of payload
             * FSMB - 0xFF SMB magic #
             */

            if (this.sbuf[0] == (byte) 0x00 && this.sbuf[4] == (byte) 0xFE && this.sbuf[5] == (byte) 'S' && this.sbuf[6] == (byte) 'M'
                    && this.sbuf[7] == (byte) 'B') {

/// tip | Dica

A coisa importante e "mágica" aqui é que `get_current_user` terá diferentes listas de `scopes` para validar para cada *operação de rota*.

/// tip | Consejo

Lo importante y "mágico" aquí es que `get_current_user` tendrá una lista diferente de `scopes` para verificar para cada *path operation*.