class_docstr: Test Search functionality.
class_docstr_tok: ["Test","Search","functionality","."]
code: def test_rag(self):
      _test_bb2_rag(
          KnowledgeAccessMethod.CLASSIFY,
          rag_model_type="token",
          n_docs=3,
          batchsize=1,
          query_generator_model_file=SEARCH_QUERY_MODEL,
          rag_retriever_type="search_engine",
          search_server=SEARCH_SERVER,
      )
  
imports: import copy
  import torch.cuda
  import unittest
  from parlai.core.agents import create_agent
  import parlai.utils.testing
label_desc: Use image node_id 1 for calling the TestBB2Search obj's underlying member method code with example usage: obj.test_rag() without return types