class_docstr: Calls to :meth:`orion.core.io.database.AbstractDB.read_and_write`.
docstr: Should return None when there is no match.
docstr_tok: ["Should","return","None","when","there","is","no","match","."]
code: def test_read_and_write_no_match(self, orion_db):
      """Should return None when there is no match."""
      loaded_config = orion_db.read_and_write(
          "experiments", {"name": "lalala"}, {"pool_size": "lalala"}
      )
  
      assert loaded_config is None
  
imports: import pickle
  from datetime import datetime
  import pytest
  from orion.core.io.database import Database, DatabaseError, DuplicateKeyError
  from orion.core.io.database.ephemeraldb import EphemeralDB
  from orion.core.io.database.mongodb import MongoDB
  from orion.core.io.database.pickleddb import PickledDB
  from .conftest import insert_test_collection
label_desc: Use image node_id 3 for calling the TestReadAndWrite obj's underlying member method code with example usage: obj.test_read_and_write_no_match(orion_db) without return types