("if-modified-since", "yesterday"),
            ("traceparent", "123"),
            ("x-tag", "one"),
            ("x-tag", "two"),
        ],
    )
    assert response.status_code == 200, response.text
    assert response.json() == {
        "host": "testserver",
        "save_data": True,
        "if_modified_since": "yesterday",
        "traceparent": "123",
        "x_tag": ["one", "two"],
    }

  # Get trace ID from TRACEPARENT, if present
  local tid
  tid="$(<<<"${TRACEPARENT:-}" cut -d- -f2)"
  tid="${tid:-"$(tr -dc 'a-f0-9' < /dev/urandom | head -c 32)"}"
  # Always generate a new span ID
  local sid
  sid="$(tr -dc 'a-f0-9' < /dev/urandom | head -c 16)"

  # Execute the command they wanted with the propagation through TRACEPARENT
  if [[ $was_execution_trace == 1 ]]; then

            ("if-modified-since", "yesterday"),
            ("traceparent", "123"),
            ("x-tag", "one"),
            ("x-tag", "two"),
        ],
    )
    assert response.status_code == 200
    assert response.json() == {
        "host": "testserver",
        "save_data": True,
        "if_modified_since": "yesterday",
        "traceparent": "123",
        "x_tag": ["one", "two"],
    }

from fastapi import FastAPI, Header
from pydantic import BaseModel

app = FastAPI()


class CommonHeaders(BaseModel):
    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: CommonHeaders = Header()):

app = FastAPI()


class CommonHeaders(BaseModel):
    model_config = {"extra": "forbid"}

    host: str
    save_data: bool
    if_modified_since: Union[str, None] = None
    traceparent: Union[str, None] = None
    x_tag: List[str] = []


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

from pydantic import BaseModel

app = FastAPI()


class CommonHeaders(BaseModel):
    class Config:
        extra = "forbid"

    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()]):

from fastapi import FastAPI, Header
from pydantic import BaseModel

app = FastAPI()


class CommonHeaders(BaseModel):
    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()]):

from fastapi import FastAPI, Header
from pydantic import BaseModel

app = FastAPI()


class CommonHeaders(BaseModel):
    host: str
    save_data: bool
    if_modified_since: Union[str, None] = None
    traceparent: Union[str, None] = None
    x_tag: list[str] = []


@app.get("/items/")
async def read_items(headers: CommonHeaders = Header()):

from fastapi import FastAPI, Header
from pydantic import BaseModel

app = FastAPI()


class CommonHeaders(BaseModel):
    host: str
    save_data: bool
    if_modified_since: Union[str, None] = None
    traceparent: Union[str, None] = None
    x_tag: List[str] = []


@app.get("/items/")
async def read_items(headers: CommonHeaders = Header()):

from fastapi import FastAPI, Header
from pydantic import BaseModel

app = FastAPI()


class CommonHeaders(BaseModel):
    host: str
    save_data: bool
    if_modified_since: Union[str, None] = None
    traceparent: Union[str, None] = None
    x_tag: list[str] = []


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