code: def post(self, *args, **kwargs):
      request_headers = kwargs.pop("headers", {})
      headers = {**self._header, **request_headers}
      return self._client.post(*args, headers=headers, **kwargs)
  
file_path: argilla/tests/integration/helpers.py
imports: from argilla._constants import API_KEY_HEADER_NAME, WORKSPACE_HEADER_NAME
  from argilla.server.models import User
  from fastapi import FastAPI
  from starlette.testclient import TestClient
label_desc: Use image node_id 6 for calling the SecuredClient obj's underlying member method code with example usage: obj.post() and returns: self