text: from haystack.database.base import Document
  
  
  def test_tfidf_retriever():
      from haystack.retriever.tfidf import TfidfRetriever
  
      test_docs = [
          {"name": "testing the finder 1", "text": "godzilla says hello"},
          {"name": "testing the finder 2", "text": "optimus prime says bye"},
          {"name": "testing the finder 3", "text": "alien says arghh"}
      ]
  
      from haystack.database.memory import InMemoryDocumentStore
      document_store = InMemoryDocumentStore()
      document_store.write_documents(test_docs)
  
      retriever = TfidfRetriever(document_store)
      retriever.fit()
      assert retriever.retrieve("godzilla", top_k=1) == [Document(id='0', text='godzilla says hello', external_source_id=None, question=None, query_score=None, meta=None)]