class_docstr: Test InMemoryDocumentStore's specific features
class_docstr_tok: ["Test","InMemoryDocumentStore","'s","specific","features"]
code: def test_bm25_retrieval(self, document_store: InMemoryDocumentStore):
      # Tests if the bm25_retrieval method returns the correct document based on the input query.
      docs = [
          Document(content="Hello world"),
          Document(content="Haystack supports multiple languages"),
      ]
      document_store.write_documents(docs)
      results = document_store.bm25_retrieval(
          query="What languages?", top_k=1
      )
      assert len(results) == 1
      assert (
          results[0].content == "Haystack supports multiple languages"
      )
  
imports: import logging
  from unittest.mock import patch
  import pandas
  import pytest
  from haystack import Document
  from haystack.document_stores.errors import DocumentStoreError, DuplicateDocumentError
  from haystack.document_stores.in_memory import InMemoryDocumentStore
  from haystack.testing.document_store import DocumentStoreBaseTests
label_desc: Use image node_id 6 for calling the TestMemoryDocumentStore obj's underlying member method code with example usage: obj.test_bm25_retrieval(document_store) without return types