ctx := context.Background()
	testCases := []struct {
		name            string
		headers         http.Header
		wantObjectAttrs map[string]struct{}
	}{
		{
			name:            "empty header",
			headers:         http.Header{},
			wantObjectAttrs: map[string]struct{}{},
		},
		{
			name: "single header line",
			headers: http.Header{
				xhttp.AmzObjectAttributes: []string{"test1,test2"},
			},

@needs_py310
@pytest.mark.parametrize(
    "path,headers,expected_status,expected_response",
    [
        ("/items", None, 200, {"X-Token values": None}),
        ("/items", {"x-token": "foo"}, 200, {"X-Token values": ["foo"]}),
        # TODO: fix this, is it a bug?
        # ("/items", [("x-token", "foo"), ("x-token", "bar")], 200, {"X-Token values": ["foo", "bar"]}),
    ],
)

}
```

### Rewriting Responses

Symmetrically, interceptors can rewrite response headers and transform the response body. This is generally more dangerous than rewriting request headers because it may violate the webserver's expectations!

	}

	// Default to remote address if headers not set.
	raddr, _, _ := net.SplitHostPort(addr)
	if raddr == "" {
		return addr
	}
	return raddr
}

// GetSourceIP retrieves the IP from the request headers
// and falls back to r.RemoteAddr when necessary.
func GetSourceIP(r *http.Request) string {
	addr := GetSourceIPRaw(r)
	if strings.ContainsRune(addr, ':') {
		return "[" + addr + "]"
	}

  forObsoleteRfc2965: Boolean,
): String = cookie.toString(forObsoleteRfc2965)

internal fun addHeaderLenient(
  builder: Headers.Builder,
  line: String,
): Headers.Builder = builder.addLenient(line)

internal fun addHeaderLenient(
  builder: Headers.Builder,
  name: String,
  value: String,
): Headers.Builder = builder.addLenient(name, value)

internal fun cacheGet(
  cache: Cache,
  request: Request,

each other, corrupt the response cache, and possibly crash your program.

Response caching uses HTTP headers for all configuration. You can add request headers like `Cache-Control: max-stale=3600` and OkHttp's cache will honor them. Your webserver configures how long responses are cached with its own response headers, like `Cache-Control: max-age=9600`. There are cache headers to force a cached response, force a network response, or force the network response to be validated with a conditional...

    host: str
    save_data: bool
    if_modified_since: str | None = None
    traceparent: str | None = None
    x_tag: list[str] = []


@app.get("/items/")
async def read_items(headers: Annotated[CommonHeaders, Header()]):

        }
    )


def test_get_invalid_one_header_items():
    response = client.get("/items/", headers={"X-Token": "invalid"})
    assert response.status_code == 400, response.text
    assert response.json() == {"detail": "X-Token header invalid"}


def test_get_invalid_one_users():
    response = client.get("/users/", headers={"X-Token": "invalid"})
    assert response.status_code == 400, response.text

    assert response.status_code == 401, response.text
    assert response.json() == {"detail": "Not authenticated"}
    assert response.headers["WWW-Authenticate"] == "Bearer"


@needs_py39
def test_token(client: TestClient):
    response = client.get("/items", headers={"Authorization": "Bearer testtoken"})
    assert response.status_code == 200, response.text
    assert response.json() == {"token": "testtoken"}

Each HTTP request contains a URL, a method (like `GET` or `POST`), and a list of headers. Requests may also contain a body: a data stream of a specific content type.

## [Responses](https://square.github.io/okhttp/4.x/okhttp/okhttp3/-response/)

The response answers the request with a code (like 200 for success or 404 for not found), headers, and its own optional body.

## Rewriting Requests