code: def test_rag_pipeline(mock_chat_completion):
      rag_pipe = build_rag_pipeline(
          document_store=InMemoryDocumentStore()
      )
      answer = rag_pipe.run(query="question")
      assert isinstance(answer, Answer)
  
file_path: haystack/test/pipelines/test_rag_pipelines.py
imports: import os
  import pytest
  from haystack.dataclasses import Answer
  from haystack.document_stores.in_memory import InMemoryDocumentStore
  from haystack.pipeline_utils.rag import build_rag_pipeline
  from haystack.testing.factory import document_store_class
label_desc: Use image node_id 1 for calling a global function with example usage: test_rag_pipeline(mock_chat_completion) without return types