code: def test_link_content_fetcher_pdf(self):
      fetcher = LinkContentFetcher()
      streams = fetcher.run([PDF_URL])["streams"]
      assert len(streams) == 1
      first_stream = streams[0]
      assert first_stream.meta["content_type"] in (
          "application/octet-stream",
          "application/pdf",
      )
      assert (
          "url" in first_stream.meta
          and first_stream.meta["url"] == PDF_URL
      )
  
file_path: haystack/test/components/fetchers/test_link_content_fetcher.py
imports: from unittest.mock import patch, Mock
  import pytest
  import requests
  from haystack.components.fetchers.link_content import LinkContentFetcher, text_content_handler, binary_content_handler, DEFAULT_USER_AGENT
label_desc: Use image node_id 9 for calling the TestLinkContentFetcher obj's underlying member method code with example usage: obj.test_link_content_fetcher_pdf() without return types