code: def test_qa(self, postgres_mock_handler):
      # create project
      self.run_sql("create database proj")
      df = pd.DataFrame.from_dict(
          {
              "context": [
                  "For adults and children age 5 and older, OTC decongestants, "
                  "antihistamines and pain relievers might offer some symptom relief. "
                  "However, they won't prevent a cold or shorten its duration, and most have some side effects.",
              ]
          }
      )
      self.set_handler(
          postgres_mock_handler, name="pg", tables={"df": df}
      )
  
      self.run_sql(
          f"""
             create model proj.test_writer_writer_qa
             from pg (select * from df)
             predict answer
             using
                  engine='writer',
                  writer_api_key='{WRITER_API_KEY}',
                  writer_org_id='{WRITER_ORG_ID}';
          """
      )
      self.wait_predictor("proj", "test_writer_writer_qa")
  
      result_df = self.run_sql(
          """
              SELECT p.answer
              FROM proj.test_writer_writer_qa as p
              WHERE question='What is the best treatment for a cold?'
          """
      )
      assert "cold" in result_df["answer"].iloc[0].lower()
  
file_path: mindsdb/tests/unit/ml_handlers/test_writer.py
imports: import os
  import time
  from unittest.mock import patch
  import pandas
  import pytest
  from mindsdb_sql import parse_sql
  from tests.unit.executor_test_base import BaseExecutorTest
label_desc: Use image node_id 6 for calling the TestWriter obj's underlying member method code with example usage: obj.test_qa(postgres_mock_handler) without return types