async def METHOD_NAME():
    async with httpx.AsyncClient(app=echo_headers) as client:
        response = await client.get("http://www.example.org/")
    assert response.status_code == 200
    assert response.json() == {
        "headers": [
            ["host", "www.example.org"],
            ["accept", "*/*"],
            ["accept-encoding", "gzip, deflate, br"],
            ["connection", "keep-alive"],
            ["user-agent", f"python-httpx/{httpx.__version__}"],
        ]
    }