def METHOD_NAME():
    url = "http://example.org/echo_headers"
    client_headers = {"User-Agent": "python-myclient/0.2.1"}
    request_headers = {"X-Auth-Token": "FooBarBazToken"}
    client = httpx.Client(
        transport=httpx.MockTransport(echo_headers), headers=client_headers
    )
    response = client.get(url, headers=request_headers)
    assert response.status_code == 200
    assert response.json() == {
        "headers": {
            "accept": "*/*",
            "accept-encoding": "gzip, deflate, br",
            "connection": "keep-alive",
            "host": "example.org",
            "user-agent": "python-myclient/0.2.1",
            "x-auth-token": "FooBarBazToken",
        }
    }